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@ -1,5 +1,5 @@ |
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<!-- |
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$Header: /cvsroot/pgsql/doc/src/sgml/arch-dev.sgml,v 2.12 2000/12/22 18:57:49 petere Exp $ |
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$Header: /cvsroot/pgsql/doc/src/sgml/arch-dev.sgml,v 2.13 2000/12/26 00:10:37 petere Exp $ |
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--> |
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<chapter id="overview"> |
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@ -284,7 +284,7 @@ select s.sname, se.pno |
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<para> |
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Figure \ref{parsetree} shows the <firstterm>parse tree</firstterm> built by the |
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grammar rules and actions given in <filename>gram.y</filename> for the query |
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given in <xref linkend="simple-select" endterm="simple-select"> |
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given in <xref linkend="simple-select"> |
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(without the <firstterm>operator tree</firstterm> for |
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the <firstterm>where clause</firstterm> which is shown in figure \ref{where_clause} |
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because there was not enough space to show both data structures in one |
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@ -312,8 +312,8 @@ select s.sname, se.pno |
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<para> |
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Figure \ref{where_clause} shows the operator tree built for the |
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where clause of the SQL query given in example |
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<xref linkend="simple-select" endterm="simple-select"> |
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where clause of the SQL query given in |
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<xref linkend="simple-select"> |
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which is attached to the field |
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<literal>qual</literal> of the <literal>SelectStmt</literal> node. The top node of the |
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operator tree is an <literal>A_Expr</literal> node representing an <literal>AND</literal> |
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