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@ -1,4 +1,4 @@ |
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<!-- $PostgreSQL: pgsql/doc/src/sgml/config.sgml,v 1.248 2010/02/01 13:40:28 sriggs Exp $ --> |
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<!-- $PostgreSQL: pgsql/doc/src/sgml/config.sgml,v 1.249 2010/02/03 17:25:05 momjian Exp $ --> |
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<chapter Id="runtime-config"> |
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<title>Server Configuration</title> |
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@ -21,10 +21,10 @@ |
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<para> |
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All parameter names are case-insensitive. Every parameter takes a |
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value of one of five types: Boolean, integer, floating point, |
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string or enum. Boolean values can be written as <literal>ON</literal>, |
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<literal>OFF</literal>, <literal>TRUE</literal>, |
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<literal>FALSE</literal>, <literal>YES</literal>, |
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<literal>NO</literal>, <literal>1</literal>, <literal>0</literal> |
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string or enum. Boolean values can be written as <literal>on</literal>, |
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<literal>off</literal>, <literal>true</literal>, |
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<literal>false</literal>, <literal>yes</literal>, |
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<literal>no</literal>, <literal>1</literal>, <literal>0</literal> |
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(all case-insensitive) or any unambiguous prefix of these. |
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</para> |
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@ -66,8 +66,8 @@ shared_buffers = 128MB |
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</programlisting> |
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One parameter is specified per line. The equal sign between name and |
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value is optional. Whitespace is insignificant and blank lines are |
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ignored. Hash marks (<literal>#</literal>) introduce comments |
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anywhere. Parameter values that are not simple identifiers or |
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ignored. Hash marks (<literal>#</literal>) designate the rest of the |
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line as a comment. Parameter values that are not simple identifiers or |
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numbers must be single-quoted. To embed a single quote in a parameter |
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value, write either two quotes (preferred) or backslash-quote. |
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</para> |
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@ -155,9 +155,9 @@ SET ENABLE_SEQSCAN TO OFF; |
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values for the parameter. Some parameters cannot be changed via |
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<command>SET</command>: for example, if they control behavior that |
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cannot be changed without restarting the entire |
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<productname>PostgreSQL</productname> server. Also, some parameters can |
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be modified via <command>SET</command> or <command>ALTER</> by superusers, |
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but not by ordinary users. |
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<productname>PostgreSQL</productname> server. Also, |
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some <command>SET</command> or <command>ALTER</> parameter modifications |
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require superuser permission. |
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</para> |
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<para> |
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@ -329,7 +329,7 @@ SET ENABLE_SEQSCAN TO OFF; |
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at all, in which case only Unix-domain sockets can be used to connect |
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to it. |
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The default value is <systemitem class="systemname">localhost</>, |
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which allows only local <quote>loopback</> connections to be |
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which allows only local TCP/IP <quote>loopback</> connections to be |
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made. While client authentication (<xref |
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linkend="client-authentication">) allows fine-grained control |
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over who can access the server, <varname>listen_addresses</varname> |
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@ -440,8 +440,8 @@ SET ENABLE_SEQSCAN TO OFF; |
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server.) In combination with the parameter |
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<varname>unix_socket_permissions</varname> this can be used as |
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an additional access control mechanism for Unix-domain connections. |
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By default this is the empty string, which selects the default |
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group for the current user. This parameter can only be set at |
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By default this is the empty string, which uses the default |
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group of the server user. This parameter can only be set at |
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server start. |
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</para> |
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</listitem> |
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@ -457,7 +457,7 @@ SET ENABLE_SEQSCAN TO OFF; |
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Sets the access permissions of the Unix-domain socket. Unix-domain |
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sockets use the usual Unix file system permission set. |
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The parameter value is expected to be a numeric mode |
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specification in the form accepted by the |
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specified in the format accepted by the |
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<function>chmod</function> and <function>umask</function> |
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system calls. (To use the customary octal format the number |
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must start with a <literal>0</literal> (zero).) |
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@ -469,7 +469,7 @@ SET ENABLE_SEQSCAN TO OFF; |
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<literal>0770</literal> (only user and group, see also |
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<varname>unix_socket_group</varname>) and <literal>0700</literal> |
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(only user). (Note that for a Unix-domain socket, only write |
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permission matters and so there is no point in setting or revoking |
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permission matters, so there is no point in setting or revoking |
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read or execute permissions.) |
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</para> |
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@ -581,7 +581,7 @@ SET ENABLE_SEQSCAN TO OFF; |
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<para> |
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Maximum time to complete client authentication, in seconds. If a |
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would-be client has not completed the authentication protocol in |
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this much time, the server breaks the connection. This prevents |
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this much time, the server closes the connection. This prevents |
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hung clients from occupying a connection indefinitely. |
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The default is one minute (<literal>1m</>). |
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This parameter can only be set in the <filename>postgresql.conf</> |
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@ -707,8 +707,9 @@ SET ENABLE_SEQSCAN TO OFF; |
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<para> |
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With this parameter enabled, you can still create ordinary global |
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users. Simply append <literal>@</> when specifying the user |
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name in the client. The <literal>@</> will be stripped off |
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before the user name is looked up by the server. |
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name in the client, e.g. <literal>joe@</>. The <literal>@</> |
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will be stripped off before the user name is looked up by the |
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server. |
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</para> |
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<para> |
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@ -783,15 +784,15 @@ SET ENABLE_SEQSCAN TO OFF; |
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session. These are session-local buffers used only for access to |
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temporary tables. The default is eight megabytes |
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(<literal>8MB</>). The setting can be changed within individual |
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sessions, but only up until the first use of temporary tables |
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within a session; subsequent attempts to change the value will |
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sessions, but only before the first use of temporary tables |
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within the session; subsequent attempts to change the value will |
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have no effect on that session. |
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</para> |
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<para> |
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A session will allocate temporary buffers as needed up to the limit |
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given by <varname>temp_buffers</>. The cost of setting a large |
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value in sessions that do not actually need a lot of temporary |
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value in sessions that do not actually need many temporary |
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buffers is only a buffer descriptor, or about 64 bytes, per |
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increment in <varname>temp_buffers</>. However if a buffer is |
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actually used an additional 8192 bytes will be consumed for it |
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@ -849,13 +850,13 @@ SET ENABLE_SEQSCAN TO OFF; |
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<listitem> |
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<para> |
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Specifies the amount of memory to be used by internal sort operations |
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and hash tables before switching to temporary disk files. The value |
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and hash tables before writing to temporary disk files. The value |
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defaults to one megabyte (<literal>1MB</>). |
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Note that for a complex query, several sort or hash operations might be |
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running in parallel; each one will be allowed to use as much memory |
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as this value specifies before it starts to put data into temporary |
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running in parallel; each operation will be allowed to use as much memory |
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as this value specifies before it starts to write data into temporary |
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files. Also, several running sessions could be doing such operations |
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concurrently. So the total memory used could be many |
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concurrently. Therefore, the total memory used could be many |
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times the value of <varname>work_mem</varname>; it is necessary to |
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keep this fact in mind when choosing the value. Sort operations are |
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used for <literal>ORDER BY</>, <literal>DISTINCT</>, and |
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@ -873,7 +874,7 @@ SET ENABLE_SEQSCAN TO OFF; |
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</indexterm> |
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<listitem> |
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<para> |
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Specifies the maximum amount of memory to be used in maintenance |
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Specifies the maximum amount of memory to be used by maintenance |
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operations, such as <command>VACUUM</command>, <command>CREATE |
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INDEX</>, and <command>ALTER TABLE ADD FOREIGN KEY</>. It defaults |
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to 16 megabytes (<literal>16MB</>). Since only one of these |
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@ -916,9 +917,9 @@ SET ENABLE_SEQSCAN TO OFF; |
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the actual kernel limit will mean that a runaway recursive function |
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can crash an individual backend process. On platforms where |
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<productname>PostgreSQL</productname> can determine the kernel limit, |
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it will not let you set this variable to an unsafe value. However, |
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not all platforms provide the information, so caution is recommended |
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in selecting a value. |
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the server will not allow this variable to be set to an unsafe |
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value. However, not all platforms provide the information, |
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so caution is recommended in selecting a value. |
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</para> |
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</listitem> |
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</varlistentry> |
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@ -942,7 +943,7 @@ SET ENABLE_SEQSCAN TO OFF; |
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a safe per-process limit, you don't need to worry about this setting. |
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But on some platforms (notably, most BSD systems), the kernel will |
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allow individual processes to open many more files than the system |
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can really support when a large number of processes all try to open |
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can actually support if many processes all try to open |
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that many files. If you find yourself seeing <quote>Too many open |
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files</> failures, try reducing this setting. |
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This parameter can only be set at server start. |
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@ -957,14 +958,14 @@ SET ENABLE_SEQSCAN TO OFF; |
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</indexterm> |
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<listitem> |
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<para> |
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This variable specifies one or more shared libraries that are |
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to be preloaded at server start. If more than one library is to be |
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loaded, separate their names with commas. For example, |
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This variable specifies one or more shared libraries |
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to be preloaded at server start. For example, |
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<literal>'$libdir/mylib'</literal> would cause |
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<literal>mylib.so</> (or on some platforms, |
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<literal>mylib.sl</>) to be preloaded from the installation's |
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standard library directory. |
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This parameter can only be set at server start. |
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If more than one library is to be loaded, separate their names |
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with commas. This parameter can only be set at server start. |
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</para> |
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<para> |
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@ -1024,15 +1025,15 @@ SET ENABLE_SEQSCAN TO OFF; |
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various I/O operations that are performed. When the accumulated |
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cost reaches a limit (specified by |
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<varname>vacuum_cost_limit</varname>), the process performing |
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the operation will sleep for a while (specified by |
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<varname>vacuum_cost_delay</varname>). Then it will reset the |
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the operation will sleep for a short period of time, as specified by |
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<varname>vacuum_cost_delay</varname>. Then it will reset the |
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counter and continue execution. |
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</para> |
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<para> |
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The intent of this feature is to allow administrators to reduce |
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the I/O impact of these commands on concurrent database |
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activity. There are many situations in which it is not very |
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activity. There are many situations where it is not |
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important that maintenance commands like |
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<command>VACUUM</command> and <command>ANALYZE</command> finish |
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quickly; however, it is usually very important that these |
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@ -1156,15 +1157,15 @@ SET ENABLE_SEQSCAN TO OFF; |
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<para> |
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There is a separate server |
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process called the <firstterm>background writer</>, whose function |
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is to issue writes of <quote>dirty</> shared buffers. The intent is |
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that server processes handling user queries should seldom or never have |
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to wait for a write to occur, because the background writer will do it. |
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However there is a net overall |
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increase in I/O load, because a repeatedly-dirtied page might |
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otherwise be written only once per checkpoint interval, but the |
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background writer might write it several times in the same interval. |
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The parameters discussed in this subsection can be used to |
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tune the behavior for local needs. |
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is to issue writes of <quote>dirty</> (new or modified) shared |
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buffers. It writes shared buffers so server processes handling |
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user queries seldom or never need to wait for a write to occur. |
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However, the background writer does cause a net overall |
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increase in I/O load, because while a repeatedly-dirtied page might |
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otherwise be written only once per checkpoint interval, the |
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background writer might write it several times as it is dirtied |
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in the same interval. The parameters discussed in this subsection |
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can be used to tune the behavior for local needs. |
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</para> |
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<variablelist> |
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@ -1329,7 +1330,9 @@ SET ENABLE_SEQSCAN TO OFF; |
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allowed to do its best in buffering, ordering, and delaying |
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writes. This can result in significantly improved performance. |
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However, if the system crashes, the results of the last few |
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committed transactions might be lost in part or whole. In the |
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committed transactions might be completely lost, or worse, |
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might appear partially committed, leaving the database in an |
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inconsistent state. In the |
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worst case, unrecoverable data corruption might occur. |
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(Crashes of the database software itself are <emphasis>not</> |
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a risk factor here. Only an operating-system-level crash |
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@ -1357,7 +1360,7 @@ SET ENABLE_SEQSCAN TO OFF; |
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</para> |
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<para> |
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This parameter can only be set in the <filename>postgresql.conf</> |
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<varname>fsync</varname> can only be set in the <filename>postgresql.conf</> |
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file or on the server command line. |
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If you turn this parameter off, also consider turning off |
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<xref linkend="guc-full-page-writes">. |
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@ -1409,7 +1412,7 @@ SET ENABLE_SEQSCAN TO OFF; |
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<para> |
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Method used for forcing WAL updates out to disk. |
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If <varname>fsync</varname> is off then this setting is irrelevant, |
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since updates will not be forced out at all. |
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since WAL file updates will not be forced out at all. |
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Possible values are: |
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</para> |
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<itemizedlist> |
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@ -1468,8 +1471,8 @@ SET ENABLE_SEQSCAN TO OFF; |
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that contains a mix of old and new data. The row-level change data |
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normally stored in WAL will not be enough to completely restore |
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such a page during post-crash recovery. Storing the full page image |
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guarantees that the page can be correctly restored, but at a price |
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in increasing the amount of data that must be written to WAL. |
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guarantees that the page can be correctly restored, but at the price |
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of increasing the amount of data that must be written to WAL. |
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(Because WAL replay always starts from a checkpoint, it is sufficient |
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to do this during the first change of each page after a checkpoint. |
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Therefore, one way to reduce the cost of full-page writes is to |
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@ -1483,7 +1486,7 @@ SET ENABLE_SEQSCAN TO OFF; |
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<varname>fsync</>, though smaller. It might be safe to turn off |
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this parameter if you have hardware (such as a battery-backed disk |
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controller) or file-system software that reduces |
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the risk of partial page writes to an acceptably low level (e.g., ReiserFS 4). |
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the risk of partial page writes to an acceptably low level (e.g., ZFS). |
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</para> |
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<para> |
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@ -1630,8 +1633,8 @@ SET ENABLE_SEQSCAN TO OFF; |
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</indexterm> |
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<listitem> |
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<para> |
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Specifies the target length of checkpoints, as a fraction of |
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the checkpoint interval. The default is 0.5. |
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Specifies the target of checkpoint completion, as a fraction of |
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total time between checkpoints. The default is 0.5. |
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This parameter can only be set in the <filename>postgresql.conf</> |
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file or on the server command line. |
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@ -1671,7 +1674,7 @@ SET ENABLE_SEQSCAN TO OFF; |
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<listitem> |
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<para> |
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When <varname>archive_mode</> is enabled, completed WAL segments |
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can be sent to archive storage by setting |
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are sent to archive storage by setting |
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<xref linkend="guc-archive-command">. |
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<varname>archive_mode</> and <varname>archive_command</> are |
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separate variables so that <varname>archive_command</> can be |
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|
@ -1688,10 +1691,10 @@ SET ENABLE_SEQSCAN TO OFF; |
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|
|
</indexterm> |
|
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|
|
<listitem> |
|
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|
|
<para> |
|
|
|
|
The shell command to execute to archive a completed segment of |
|
|
|
|
the WAL file series. Any <literal>%p</> in the string is |
|
|
|
|
The shell command to execute to archive a completed WAL file |
|
|
|
|
segment. Any <literal>%p</> in the string is |
|
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|
|
replaced by the path name of the file to archive, and any |
|
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|
|
<literal>%f</> is replaced by the file name only. |
|
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|
|
<literal>%f</> is replaced by only the file name. |
|
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|
|
(The path name is relative to the working directory of the server, |
|
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|
|
i.e., the cluster's data directory.) |
|
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|
|
Use <literal>%%</> to embed an actual <literal>%</> character in the |
|
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|
|
@ -1701,9 +1704,13 @@ SET ENABLE_SEQSCAN TO OFF; |
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|
|
file or on the server command line. It is ignored unless |
|
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|
|
<varname>archive_mode</> was enabled at server start. |
|
|
|
|
If <varname>archive_command</> is an empty string (the default) while |
|
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|
|
<varname>archive_mode</> is enabled, then WAL archiving is temporarily |
|
|
|
|
<varname>archive_mode</> is enabled, WAL archiving is temporarily |
|
|
|
|
disabled, but the server continues to accumulate WAL segment files in |
|
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|
|
the expectation that a command will soon be provided. |
|
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|
|
the expectation that a command will soon be provided. Setting |
|
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|
|
<varname>archive_mode</> to a command that does nothing but |
|
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|
|
return true, e.g. <literal>/bin/true</>, effectively disables |
|
|
|
|
archiving, but also breaks the chain of WAL files needed for |
|
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|
|
archive recovery, so it should only be used in unusual circumstances. |
|
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|
|
</para> |
|
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|
|
<para> |
|
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|
|
It is important for the command to return a zero exit status if |
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|
|
@ -1723,11 +1730,11 @@ archive_command = 'copy "%p" "C:\\server\\archivedir\\%f"' # Windows |
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|
</indexterm> |
|
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|
|
<listitem> |
|
|
|
|
<para> |
|
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|
|
The <xref linkend="guc-archive-command"> is only invoked on |
|
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|
|
The <xref linkend="guc-archive-command"> is only invoked for |
|
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|
|
completed WAL segments. Hence, if your server generates little WAL |
|
|
|
|
traffic (or has slack periods where it does so), there could be a |
|
|
|
|
long delay between the completion of a transaction and its safe |
|
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|
|
recording in archive storage. To put a limit on how old unarchived |
|
|
|
|
recording in archive storage. To limit how old unarchived |
|
|
|
|
data can be, you can set <varname>archive_timeout</> to force the |
|
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|
|
server to switch to a new WAL segment file periodically. When this |
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|
|
parameter is greater than zero, the server will switch to a new |
|
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|
|
@ -1854,16 +1861,15 @@ archive_command = 'copy "%p" "C:\\server\\archivedir\\%f"' # Windows |
|
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|
|
These configuration parameters provide a crude method of |
|
|
|
|
influencing the query plans chosen by the query optimizer. If |
|
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|
|
the default plan chosen by the optimizer for a particular query |
|
|
|
|
is not optimal, a temporary solution can be found by using one |
|
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|
|
is not optimal, a <emphasis>temporary</> solution is to use one |
|
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|
|
of these configuration parameters to force the optimizer to |
|
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|
|
choose a different plan. Turning one of these settings off |
|
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|
|
permanently is seldom a good idea, however. |
|
|
|
|
choose a different plan. |
|
|
|
|
Better ways to improve the quality of the |
|
|
|
|
plans chosen by the optimizer include adjusting the <xref |
|
|
|
|
linkend="runtime-config-query-constants" |
|
|
|
|
endterm="runtime-config-query-constants-title">, running <xref |
|
|
|
|
linkend="sql-analyze" endterm="sql-analyze-title"> more |
|
|
|
|
frequently, increasing the value of the <xref |
|
|
|
|
endterm="runtime-config-query-constants-title">, running <xref |
|
|
|
|
linkend="sql-analyze" endterm="sql-analyze-title"> manually, increasing |
|
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|
|
the value of the <xref |
|
|
|
|
linkend="guc-default-statistics-target"> configuration parameter, |
|
|
|
|
and increasing the amount of statistics collected for |
|
|
|
|
specific columns using <command>ALTER TABLE SET |
|
|
|
|
@ -1950,7 +1956,7 @@ archive_command = 'copy "%p" "C:\\server\\archivedir\\%f"' # Windows |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
Enables or disables the query planner's use of nested-loop join |
|
|
|
|
plans. It's not possible to suppress nested-loop joins entirely, |
|
|
|
|
plans. It is impossible to suppress nested-loop joins entirely, |
|
|
|
|
but turning this variable off discourages the planner from using |
|
|
|
|
one if there are other methods available. The default is |
|
|
|
|
<literal>on</>. |
|
|
|
|
@ -1969,7 +1975,7 @@ archive_command = 'copy "%p" "C:\\server\\archivedir\\%f"' # Windows |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
Enables or disables the query planner's use of sequential scan |
|
|
|
|
plan types. It's not possible to suppress sequential scans |
|
|
|
|
plan types. It is impossible to suppress sequential scans |
|
|
|
|
entirely, but turning this variable off discourages the planner |
|
|
|
|
from using one if there are other methods available. The |
|
|
|
|
default is <literal>on</>. |
|
|
|
|
@ -1985,7 +1991,7 @@ archive_command = 'copy "%p" "C:\\server\\archivedir\\%f"' # Windows |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
Enables or disables the query planner's use of explicit sort |
|
|
|
|
steps. It's not possible to suppress explicit sorts entirely, |
|
|
|
|
steps. It is impossible to suppress explicit sorts entirely, |
|
|
|
|
but turning this variable off discourages the planner from |
|
|
|
|
using one if there are other methods available. The default |
|
|
|
|
is <literal>on</>. |
|
|
|
|
@ -2017,8 +2023,8 @@ archive_command = 'copy "%p" "C:\\server\\archivedir\\%f"' # Windows |
|
|
|
|
The <firstterm>cost</> variables described in this section are measured |
|
|
|
|
on an arbitrary scale. Only their relative values matter, hence |
|
|
|
|
scaling them all up or down by the same factor will result in no change |
|
|
|
|
in the planner's choices. Traditionally, these variables have been |
|
|
|
|
referenced to sequential page fetches as the unit of cost; that is, |
|
|
|
|
in the planner's choices. By default, these cost variables are based on |
|
|
|
|
the cost of sequential page fetches; that is, |
|
|
|
|
<varname>seq_page_cost</> is conventionally set to <literal>1.0</> |
|
|
|
|
and the other cost variables are set with reference to that. But |
|
|
|
|
you can use a different scale if you prefer, such as actual execution |
|
|
|
|
@ -2029,7 +2035,7 @@ archive_command = 'copy "%p" "C:\\server\\archivedir\\%f"' # Windows |
|
|
|
|
<para> |
|
|
|
|
Unfortunately, there is no well-defined method for determining ideal |
|
|
|
|
values for the cost variables. They are best treated as averages over |
|
|
|
|
the entire mix of queries that a particular installation will get. This |
|
|
|
|
the entire mix of queries that a particular installation will receive. This |
|
|
|
|
means that changing them on the basis of just a few experiments is very |
|
|
|
|
risky. |
|
|
|
|
</para> |
|
|
|
|
@ -2193,8 +2199,8 @@ archive_command = 'copy "%p" "C:\\server\\archivedir\\%f"' # Windows |
|
|
|
|
<para> |
|
|
|
|
Enables or disables genetic query optimization. |
|
|
|
|
This is on by default. It is usually best not to turn it off in |
|
|
|
|
production; the <varname>geqo_threshold</varname> variable provides a |
|
|
|
|
more granular way to control use of GEQO. |
|
|
|
|
production; the <varname>geqo_threshold</varname> variable provides |
|
|
|
|
more granular control of GEQO. |
|
|
|
|
</para> |
|
|
|
|
</listitem> |
|
|
|
|
</varlistentry> |
|
|
|
|
@ -2211,7 +2217,8 @@ archive_command = 'copy "%p" "C:\\server\\archivedir\\%f"' # Windows |
|
|
|
|
<literal>FULL OUTER JOIN</> construct counts as only one <literal>FROM</> |
|
|
|
|
item.) The default is 12. For simpler queries it is usually best |
|
|
|
|
to use the deterministic, exhaustive planner, but for queries with |
|
|
|
|
many tables the deterministic planner takes too long. |
|
|
|
|
many tables the deterministic planner takes too long, often |
|
|
|
|
longer than the penalty of executing a suboptimal plan. |
|
|
|
|
</para> |
|
|
|
|
</listitem> |
|
|
|
|
</varlistentry> |
|
|
|
|
@ -2320,8 +2327,8 @@ archive_command = 'copy "%p" "C:\\server\\archivedir\\%f"' # Windows |
|
|
|
|
</indexterm> |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
Sets the default statistics target for table columns that have |
|
|
|
|
not had a column-specific target set via <command>ALTER TABLE |
|
|
|
|
Sets the default statistics target for table columns without |
|
|
|
|
a column-specific target set via <command>ALTER TABLE |
|
|
|
|
SET STATISTICS</>. Larger values increase the time needed to |
|
|
|
|
do <command>ANALYZE</>, but might improve the quality of the |
|
|
|
|
planner's estimates. The default is 100. For more information |
|
|
|
|
@ -2349,7 +2356,9 @@ archive_command = 'copy "%p" "C:\\server\\archivedir\\%f"' # Windows |
|
|
|
|
<literal>partition</> (examine constraints only for inheritance child |
|
|
|
|
tables and <literal>UNION ALL</> subqueries). |
|
|
|
|
<literal>partition</> is the default setting. |
|
|
|
|
</para> |
|
|
|
|
It is often used with inheritance and partitioned tables to |
|
|
|
|
improve performance. |
|
|
|
|
</para> |
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
|
When this parameter allows it for a particular table, the planner |
|
|
|
|
@ -2366,9 +2375,7 @@ SELECT * FROM parent WHERE key = 2400; |
|
|
|
|
</programlisting> |
|
|
|
|
|
|
|
|
|
With constraint exclusion enabled, this <command>SELECT</> |
|
|
|
|
will not scan <structname>child1000</> at all. This can |
|
|
|
|
improve performance when inheritance is used to build |
|
|
|
|
partitioned tables. |
|
|
|
|
will not scan <structname>child1000</> at all, improving performance. |
|
|
|
|
</para> |
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
|
@ -2449,8 +2456,8 @@ SELECT * FROM parent WHERE key = 2400; |
|
|
|
|
for most uses. Setting it to 1 prevents any reordering of |
|
|
|
|
explicit <literal>JOIN</>s. Thus, the explicit join order |
|
|
|
|
specified in the query will be the actual order in which the |
|
|
|
|
relations are joined. The query planner does not always choose |
|
|
|
|
the optimal join order; advanced users can elect to |
|
|
|
|
relations are joined. Because the query planner does not always choose |
|
|
|
|
the optimal join order, advanced users can elect to |
|
|
|
|
temporarily set this variable to 1, and then specify the join |
|
|
|
|
order they desire explicitly. |
|
|
|
|
For more information see <xref linkend="explicit-joins">. |
|
|
|
|
@ -2505,7 +2512,8 @@ SELECT * FROM parent WHERE key = 2400; |
|
|
|
|
<para> |
|
|
|
|
If <systemitem>csvlog</> is included in <varname>log_destination</>, |
|
|
|
|
log entries are output in <quote>comma separated |
|
|
|
|
value</> format, which is convenient for loading them into programs. |
|
|
|
|
value</> (<acronym>CSV</>) format, which is convenient for |
|
|
|
|
loading logs into programs. |
|
|
|
|
See <xref linkend="runtime-config-logging-csvlog"> for details. |
|
|
|
|
<varname>logging_collector</varname> must be enabled to generate |
|
|
|
|
CSV-format log output. |
|
|
|
|
@ -2521,7 +2529,7 @@ SELECT * FROM parent WHERE key = 2400; |
|
|
|
|
<literal>LOCAL0</> through <literal>LOCAL7</> (see <xref |
|
|
|
|
linkend="guc-syslog-facility">), but the default |
|
|
|
|
<application>syslog</application> configuration on most platforms |
|
|
|
|
will discard all such messages. You will need to add something like |
|
|
|
|
will discard all such messages. You will need to add something like: |
|
|
|
|
<programlisting> |
|
|
|
|
local0.* /var/log/postgresql |
|
|
|
|
</programlisting> |
|
|
|
|
@ -2539,9 +2547,8 @@ local0.* /var/log/postgresql |
|
|
|
|
</indexterm> |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
This parameter allows messages sent to <application>stderr</>, |
|
|
|
|
and CSV-format log output, to be |
|
|
|
|
captured and redirected into log files. |
|
|
|
|
This parameter captures plain and CSV-format log messages |
|
|
|
|
sent to <application>stderr</> and redirects them into log files. |
|
|
|
|
This approach is often more useful than |
|
|
|
|
logging to <application>syslog</>, since some types of messages |
|
|
|
|
might not appear in <application>syslog</> output (a common example |
|
|
|
|
@ -2832,7 +2839,11 @@ local0.* /var/log/postgresql |
|
|
|
|
Controls the amount of detail written in the server log for each |
|
|
|
|
message that is logged. Valid values are <literal>TERSE</>, |
|
|
|
|
<literal>DEFAULT</>, and <literal>VERBOSE</>, each adding more |
|
|
|
|
fields to displayed messages. |
|
|
|
|
fields to displayed messages. <literal>VERBOSE</> logging |
|
|
|
|
output includes the <link |
|
|
|
|
linkend="errcodes-appendix">SQLSTATE</> error |
|
|
|
|
code and the source code file name, function name, |
|
|
|
|
and line number that generated the error. |
|
|
|
|
Only superusers can change this setting. |
|
|
|
|
</para> |
|
|
|
|
</listitem> |
|
|
|
|
@ -2845,8 +2856,8 @@ local0.* /var/log/postgresql |
|
|
|
|
</indexterm> |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
Controls whether or not the SQL statement that causes an error |
|
|
|
|
condition will be recorded in the server log. The current |
|
|
|
|
Controls which SQL statements that cause an error |
|
|
|
|
condition are recorded in the server log. The current |
|
|
|
|
SQL statement is included in the log entry for any message of |
|
|
|
|
the specified severity or higher. |
|
|
|
|
Valid values are <literal>DEBUG5</literal>, |
|
|
|
|
@ -3165,7 +3176,7 @@ local0.* /var/log/postgresql |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
By default, connection log messages only show the IP address of the |
|
|
|
|
connecting host. Turning on this parameter causes logging of the |
|
|
|
|
connecting host. Turning this parameter on causes logging of the |
|
|
|
|
host name as well. Note that depending on your host name resolution |
|
|
|
|
setup this might impose a non-negligible performance penalty. |
|
|
|
|
This parameter can only be set in the <filename>postgresql.conf</> |
|
|
|
|
@ -3312,7 +3323,7 @@ FROM pg_stat_activity; |
|
|
|
|
If you set a nonempty value for <varname>log_line_prefix</>, |
|
|
|
|
you should usually make its last character be a space, to provide |
|
|
|
|
visual separation from the rest of the log line. A punctuation |
|
|
|
|
character could be used too. |
|
|
|
|
character can be used too. |
|
|
|
|
</para> |
|
|
|
|
</tip> |
|
|
|
|
|
|
|
|
|
@ -3392,11 +3403,11 @@ FROM pg_stat_activity; |
|
|
|
|
</indexterm> |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
Controls logging of use of temporary files. |
|
|
|
|
Controls logging of temporary file names and sizes. |
|
|
|
|
Temporary files can be |
|
|
|
|
created for sorts, hashes, and temporary query results. |
|
|
|
|
A log entry is made for each temporary file when it is deleted. |
|
|
|
|
A value of zero logs all temporary files, while positive |
|
|
|
|
A value of zero logs all temporary file information, while positive |
|
|
|
|
values log only files whose size is greater than or equal to |
|
|
|
|
the specified number of kilobytes. The |
|
|
|
|
default setting is <literal>-1</>, which disables such logging. |
|
|
|
|
@ -3415,7 +3426,7 @@ FROM pg_stat_activity; |
|
|
|
|
Sets the time zone used for timestamps written in the log. |
|
|
|
|
Unlike <xref linkend="guc-timezone">, this value is cluster-wide, |
|
|
|
|
so that all sessions will report timestamps consistently. |
|
|
|
|
The default is <literal>unknown</>, which means to use whatever |
|
|
|
|
The default is <literal>unknown</>, which means use whatever |
|
|
|
|
the system environment specifies as the time zone. See <xref |
|
|
|
|
linkend="datatype-timezones"> for more information. |
|
|
|
|
This parameter can only be set in the <filename>postgresql.conf</> |
|
|
|
|
@ -3432,7 +3443,8 @@ FROM pg_stat_activity; |
|
|
|
|
<para> |
|
|
|
|
Including <literal>csvlog</> in the <varname>log_destination</> list |
|
|
|
|
provides a convenient way to import log files into a database table. |
|
|
|
|
This option emits log lines in comma-separated-value format, |
|
|
|
|
This option emits log lines in comma-separated-values |
|
|
|
|
(<acronym>CSV</>) format, |
|
|
|
|
with these columns: |
|
|
|
|
timestamp with milliseconds, |
|
|
|
|
user name, |
|
|
|
|
@ -3503,7 +3515,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; |
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
|
There are a few things you need to do to simplify importing CSV log |
|
|
|
|
files easily and automatically: |
|
|
|
|
files: |
|
|
|
|
|
|
|
|
|
<orderedlist> |
|
|
|
|
<listitem> |
|
|
|
|
@ -3575,11 +3587,11 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
Enables the collection of information on the currently |
|
|
|
|
executing command of each session, along with the time at |
|
|
|
|
which that command began execution. This parameter is on by |
|
|
|
|
executing command of each session, along with the time when |
|
|
|
|
that command began execution. This parameter is on by |
|
|
|
|
default. Note that even when enabled, this information is not |
|
|
|
|
visible to all users, only to superusers and the user owning |
|
|
|
|
the session being reported on; so it should not represent a |
|
|
|
|
the session being reported on, so it should not represent a |
|
|
|
|
security risk. |
|
|
|
|
Only superusers can change this setting. |
|
|
|
|
</para> |
|
|
|
|
@ -3666,8 +3678,8 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; |
|
|
|
|
<para> |
|
|
|
|
Sets the directory to store temporary statistics data in. This can be |
|
|
|
|
a path relative to the data directory or an absolute path. The default |
|
|
|
|
is <filename>pg_stat_tmp</filename>. Pointing this at a RAM based |
|
|
|
|
filesystem will decrease physical I/O requirements and can lead to |
|
|
|
|
is <filename>pg_stat_tmp</filename>. Pointing this at a RAM-based |
|
|
|
|
file system will decrease physical I/O requirements and can lead to |
|
|
|
|
improved performance. |
|
|
|
|
This parameter can only be set in the <filename>postgresql.conf</> |
|
|
|
|
file or on the server command line. |
|
|
|
|
@ -3701,9 +3713,10 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; |
|
|
|
|
</indexterm> |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
For each query, write performance statistics of the respective |
|
|
|
|
For each query, output performance statistics of the respective |
|
|
|
|
module to the server log. This is a crude profiling |
|
|
|
|
instrument. <varname>log_statement_stats</varname> reports total |
|
|
|
|
instrument, similar to the Unix <function>getrusage()</> operating |
|
|
|
|
system facility. <varname>log_statement_stats</varname> reports total |
|
|
|
|
statement statistics, while the others report per-module statistics. |
|
|
|
|
<varname>log_statement_stats</varname> cannot be enabled together with |
|
|
|
|
any of the per-module options. All of these options are disabled by |
|
|
|
|
@ -3742,7 +3755,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; |
|
|
|
|
<para> |
|
|
|
|
Controls whether the server should run the |
|
|
|
|
autovacuum launcher daemon. This is on by default; however, |
|
|
|
|
<xref linkend="guc-track-counts"> must also be turned on for |
|
|
|
|
<xref linkend="guc-track-counts"> must also be enabled for |
|
|
|
|
autovacuum to work. |
|
|
|
|
This parameter can only be set in the <filename>postgresql.conf</> |
|
|
|
|
file or on the server command line. |
|
|
|
|
@ -3800,7 +3813,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; |
|
|
|
|
database. In each round the daemon examines the |
|
|
|
|
database and issues <command>VACUUM</> and <command>ANALYZE</> commands |
|
|
|
|
as needed for tables in that database. The delay is measured |
|
|
|
|
in seconds, and the default is one minute (<literal>1m</>). |
|
|
|
|
in seconds, and the default is one minute (<literal>1min</>). |
|
|
|
|
This parameter can only be set in the <filename>postgresql.conf</> |
|
|
|
|
file or on the server command line. |
|
|
|
|
</para> |
|
|
|
|
@ -3965,7 +3978,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; |
|
|
|
|
<para> |
|
|
|
|
This variable specifies the order in which schemas are searched |
|
|
|
|
when an object (table, data type, function, etc.) is referenced by a |
|
|
|
|
simple name with no schema component. When there are objects of |
|
|
|
|
simple name with no schema specified. When there are objects of |
|
|
|
|
identical names in different schemas, the one found first |
|
|
|
|
in the search path is used. An object that is not in any of the |
|
|
|
|
schemas in the search path can only be referenced by specifying |
|
|
|
|
@ -3973,7 +3986,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; |
|
|
|
|
</para> |
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
|
The value for <varname>search_path</varname> has to be a comma-separated |
|
|
|
|
The value for <varname>search_path</varname> must be a comma-separated |
|
|
|
|
list of schema names. If one of the list items is |
|
|
|
|
the special value <literal>$user</literal>, then the schema |
|
|
|
|
having the name returned by <function>SESSION_USER</> is substituted, if there |
|
|
|
|
@ -3993,9 +4006,9 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; |
|
|
|
|
<literal>pg_temp_<replaceable>nnn</></>, is always searched if it |
|
|
|
|
exists. It can be explicitly listed in the path by using the |
|
|
|
|
alias <literal>pg_temp</>. If it is not listed in the path then |
|
|
|
|
it is searched first (before even <literal>pg_catalog</>). However, |
|
|
|
|
it is searched first (even before <literal>pg_catalog</>). However, |
|
|
|
|
the temporary schema is only searched for relation (table, view, |
|
|
|
|
sequence, etc) and data type names. It will never be searched for |
|
|
|
|
sequence, etc) and data type names. It is never searched for |
|
|
|
|
function or operator names. |
|
|
|
|
</para> |
|
|
|
|
|
|
|
|
|
@ -4022,7 +4035,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; |
|
|
|
|
via the <acronym>SQL</acronym> function |
|
|
|
|
<function>current_schemas()</>. This is not quite the same as |
|
|
|
|
examining the value of <varname>search_path</varname>, since |
|
|
|
|
<function>current_schemas()</> shows how the requests |
|
|
|
|
<function>current_schemas()</> shows how the items |
|
|
|
|
appearing in <varname>search_path</varname> were resolved. |
|
|
|
|
</para> |
|
|
|
|
|
|
|
|
|
@ -4075,11 +4088,11 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; |
|
|
|
|
<indexterm><primary>tablespace</><secondary>temporary</></> |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
This variable specifies tablespace(s) in which to create temporary |
|
|
|
|
This variable specifies tablespaces in which to create temporary |
|
|
|
|
objects (temp tables and indexes on temp tables) when a |
|
|
|
|
<command>CREATE</> command does not explicitly specify a tablespace. |
|
|
|
|
Temporary files for purposes such as sorting large data sets |
|
|
|
|
are also created in these tablespace(s). |
|
|
|
|
are also created in these tablespaces. |
|
|
|
|
</para> |
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
|
@ -4210,8 +4223,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; |
|
|
|
|
milliseconds, starting from the time the command arrives at the server |
|
|
|
|
from the client. If <varname>log_min_error_statement</> is set to |
|
|
|
|
<literal>ERROR</> or lower, the statement that timed out will also be |
|
|
|
|
logged. A value of zero (the default) turns off the |
|
|
|
|
limitation. |
|
|
|
|
logged. A value of zero (the default) turns this off. |
|
|
|
|
</para> |
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
|
@ -4527,7 +4539,9 @@ SET XML OPTION { DOCUMENT | CONTENT }; |
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
|
Only superusers can change this setting, because it affects the |
|
|
|
|
messages sent to the server log as well as to the client. |
|
|
|
|
messages sent to the server log as well as to the client, and |
|
|
|
|
an improper value might obscure the readability of the server |
|
|
|
|
logs. |
|
|
|
|
</para> |
|
|
|
|
</listitem> |
|
|
|
|
</varlistentry> |
|
|
|
|
@ -4631,12 +4645,12 @@ SET XML OPTION { DOCUMENT | CONTENT }; |
|
|
|
|
</para> |
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
|
The value for <varname>dynamic_library_path</varname> has to be a |
|
|
|
|
The value for <varname>dynamic_library_path</varname> must be a |
|
|
|
|
list of absolute directory paths separated by colons (or semi-colons |
|
|
|
|
on Windows). If a list element starts |
|
|
|
|
with the special string <literal>$libdir</literal>, the |
|
|
|
|
compiled-in <productname>PostgreSQL</productname> package |
|
|
|
|
library directory is substituted for <literal>$libdir</literal>. This |
|
|
|
|
library directory is substituted for <literal>$libdir</literal>; this |
|
|
|
|
is where the modules provided by the standard |
|
|
|
|
<productname>PostgreSQL</productname> distribution are installed. |
|
|
|
|
(Use <literal>pg_config --pkglibdir</literal> to find out the name of |
|
|
|
|
@ -4674,7 +4688,7 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' |
|
|
|
|
</indexterm> |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
Soft upper limit of the size of the set returned by GIN index. For more |
|
|
|
|
Soft upper limit of the size of the set returned by GIN index scans. For more |
|
|
|
|
information see <xref linkend="gin-tips">. |
|
|
|
|
</para> |
|
|
|
|
</listitem> |
|
|
|
|
@ -4711,7 +4725,8 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' |
|
|
|
|
</para> |
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
|
There is no performance advantage to loading a library at session |
|
|
|
|
Unlike <varname>local_preload_libraries</>, there is no |
|
|
|
|
performance advantage to loading a library at session |
|
|
|
|
start rather than when it is first used. Rather, the intent of |
|
|
|
|
this feature is to allow debugging or performance-measurement |
|
|
|
|
libraries to be loaded into specific sessions without an explicit |
|
|
|
|
@ -4761,10 +4776,10 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' |
|
|
|
|
<para> |
|
|
|
|
This is the amount of time, in milliseconds, to wait on a lock |
|
|
|
|
before checking to see if there is a deadlock condition. The |
|
|
|
|
check for deadlock is relatively slow, so the server doesn't run |
|
|
|
|
check for deadlock is relatively expensive, so the server doesn't run |
|
|
|
|
it every time it waits for a lock. We optimistically assume |
|
|
|
|
that deadlocks are not common in production applications and |
|
|
|
|
just wait on the lock for a while before starting the check for a |
|
|
|
|
just wait on the lock for a while before checking for a |
|
|
|
|
deadlock. Increasing this value reduces the amount of time |
|
|
|
|
wasted in needless deadlock checks, but slows down reporting of |
|
|
|
|
real deadlock errors. The default is one second (<literal>1s</>), |
|
|
|
|
@ -4792,7 +4807,7 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' |
|
|
|
|
</indexterm> |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
The shared lock table is created to track locks on |
|
|
|
|
The shared lock table tracks locks on |
|
|
|
|
<varname>max_locks_per_transaction</varname> * (<xref |
|
|
|
|
linkend="guc-max-connections"> + <xref |
|
|
|
|
linkend="guc-max-prepared-transactions">) objects (e.g., tables); |
|
|
|
|
@ -4889,7 +4904,7 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' |
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
|
Note that in a standard-conforming string literal, <literal>\</> just |
|
|
|
|
means <literal>\</> anyway. This parameter affects the handling of |
|
|
|
|
means <literal>\</> anyway. This parameter only affects the handling of |
|
|
|
|
non-standard-conforming literals, including |
|
|
|
|
escape string syntax (<literal>E'...'</>). |
|
|
|
|
</para> |
|
|
|
|
@ -4908,9 +4923,8 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' |
|
|
|
|
newly-created tables, if neither <literal>WITH OIDS</literal> |
|
|
|
|
nor <literal>WITHOUT OIDS</literal> is specified. It also |
|
|
|
|
determines whether OIDs will be included in tables created by |
|
|
|
|
<command>SELECT INTO</command>. In <productname>PostgreSQL</> |
|
|
|
|
8.1 <varname>default_with_oids</> is <literal>off</> by default; in |
|
|
|
|
prior versions of <productname>PostgreSQL</productname>, it |
|
|
|
|
<command>SELECT INTO</command>. The parameter is <literal>off</> |
|
|
|
|
by default; in <productname>PostgreSQL</> 8.0 and earlier, it |
|
|
|
|
was on by default. |
|
|
|
|
</para> |
|
|
|
|
|
|
|
|
|
@ -4983,7 +4997,7 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' |
|
|
|
|
<listitem> |
|
|
|
|
<para> |
|
|
|
|
This controls the inheritance semantics. If turned <literal>off</>, |
|
|
|
|
subtables are not included by various commands by default; basically |
|
|
|
|
subtables are not accessed by various commands by default; basically |
|
|
|
|
an implied <literal>ONLY</literal> key word. This was added for |
|
|
|
|
compatibility with releases prior to 7.1. See |
|
|
|
|
<xref linkend="ddl-inherit"> for more information. |
|
|
|
|
@ -5006,12 +5020,13 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' |
|
|
|
|
<productname>PostgreSQL</productname> to have its historical |
|
|
|
|
behavior of treating backslashes as escape characters. |
|
|
|
|
The default will change to <literal>on</> in a future release |
|
|
|
|
to improve compatibility with the standard. |
|
|
|
|
to improve compatibility with the SQL standard. |
|
|
|
|
Applications can check this |
|
|
|
|
parameter to determine how string literals will be processed. |
|
|
|
|
The presence of this parameter can also be taken as an indication |
|
|
|
|
that the escape string syntax (<literal>E'...'</>) is supported. |
|
|
|
|
Escape string syntax should be used if an application desires |
|
|
|
|
Escape string syntax (<xref linkend="sql-syntax-strings-escape">) |
|
|
|
|
should be used if an application desires |
|
|
|
|
backslashes to be treated as escape characters. |
|
|
|
|
</para> |
|
|
|
|
</listitem> |
|
|
|
|
@ -5072,11 +5087,11 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' |
|
|
|
|
null values, so if you use that interface to access the database you |
|
|
|
|
might want to turn this option on. Since expressions of the |
|
|
|
|
form <literal><replaceable>expr</> = NULL</literal> always |
|
|
|
|
return the null value (using the correct interpretation) they are not |
|
|
|
|
very useful and do not appear often in normal applications, so |
|
|
|
|
return the null value (using the SQL standard interpretation), they are not |
|
|
|
|
very useful and do not appear often in normal applications so |
|
|
|
|
this option does little harm in practice. But new users are |
|
|
|
|
frequently confused about the semantics of expressions |
|
|
|
|
involving null values, so this option is not on by default. |
|
|
|
|
involving null values, so this option is off by default. |
|
|
|
|
</para> |
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
|
@ -5200,7 +5215,8 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' |
|
|
|
|
less than the value of <literal>NAMEDATALEN</> when building |
|
|
|
|
the server. The default value of <literal>NAMEDATALEN</> is |
|
|
|
|
64; therefore the default |
|
|
|
|
<varname>max_identifier_length</varname> is 63 bytes. |
|
|
|
|
<varname>max_identifier_length</varname> is 63 bytes, which |
|
|
|
|
can be less than 63 characters when using multi-byte encodings. |
|
|
|
|
</para> |
|
|
|
|
</listitem> |
|
|
|
|
</varlistentry> |
|
|
|
|
@ -5355,8 +5371,7 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' |
|
|
|
|
module for a specific class is loaded, it will add the proper variable |
|
|
|
|
definitions for its class name, convert any placeholder |
|
|
|
|
values according to those definitions, and issue warnings for any |
|
|
|
|
placeholders of its class that remain (which presumably would be |
|
|
|
|
misspelled configuration variables). |
|
|
|
|
unrecognized placeholders of its class that remain. |
|
|
|
|
</para> |
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
|
@ -5377,9 +5392,9 @@ plruby.use_strict = true # generates error: unknown class name |
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
|
The following parameters are intended for work on the |
|
|
|
|
<productname>PostgreSQL</productname> source, and in some cases |
|
|
|
|
<productname>PostgreSQL</productname> source code, and in some cases |
|
|
|
|
to assist with recovery of severely damaged databases. There |
|
|
|
|
should be no reason to use them in a production database setup. |
|
|
|
|
should be no reason to use them on a production database. |
|
|
|
|
As such, they have been excluded from the sample |
|
|
|
|
<filename>postgresql.conf</> file. Note that many of these |
|
|
|
|
parameters require special source compilation flags to work at all. |
|
|
|
|
@ -5445,7 +5460,7 @@ plruby.use_strict = true # generates error: unknown class name |
|
|
|
|
<para> |
|
|
|
|
If nonzero, a delay of this many seconds occurs when a new |
|
|
|
|
server process is started, after it conducts the |
|
|
|
|
authentication procedure. This is intended to give an |
|
|
|
|
authentication procedure. This is intended to give developers an |
|
|
|
|
opportunity to attach to the server process with a debugger. |
|
|
|
|
This parameter cannot be changed after session start. |
|
|
|
|
</para> |
|
|
|
|
@ -5461,7 +5476,7 @@ plruby.use_strict = true # generates error: unknown class name |
|
|
|
|
<para> |
|
|
|
|
If nonzero, a delay of this many seconds occurs just after a |
|
|
|
|
new server process is forked, before it conducts the |
|
|
|
|
authentication procedure. This is intended to give an |
|
|
|
|
authentication procedure. This is intended to give developers an |
|
|
|
|
opportunity to attach to the server process with a debugger to |
|
|
|
|
trace down misbehavior in authentication. |
|
|
|
|
This parameter can only be set in the <filename>postgresql.conf</> |
|
|
|
|
@ -5482,7 +5497,7 @@ plruby.use_strict = true # generates error: unknown class name |
|
|
|
|
commands. <xref linkend="guc-client-min-messages"> or |
|
|
|
|
<xref linkend="guc-log-min-messages"> must be |
|
|
|
|
<literal>DEBUG1</literal> or lower to send this output to the |
|
|
|
|
client or server log, respectively. |
|
|
|
|
client or server logs, respectively. |
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</para> |
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</listitem> |
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</varlistentry> |
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@ -5719,9 +5734,9 @@ plruby.use_strict = true # generates error: unknown class name |
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namely all the rows on the damaged page. But it allows you to get |
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past the error and retrieve rows from any undamaged pages that might |
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be present in the table. So it is useful for recovering data if |
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corruption has occurred due to hardware or software error. You should |
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corruption has occurred due to a hardware or software error. You should |
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generally not set this on until you have given up hope of recovering |
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data from the damaged page(s) of a table. The |
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data from the damaged pages of a table. The |
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default setting is <literal>off</>, and it can only be changed |
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by a superuser. |
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</para> |
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Bruce Momjian
16 years ago