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@ -1,10 +1,14 @@ |
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<!-- |
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$Header: /cvsroot/pgsql/doc/src/sgml/extend.sgml,v 1.17 2002/09/21 18:32:53 petere Exp $ |
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$Header: /cvsroot/pgsql/doc/src/sgml/extend.sgml,v 1.18 2002/11/03 01:31:32 momjian Exp $ |
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--> |
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<chapter id="extend"> |
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<title>Extending <acronym>SQL</acronym>: An Overview</title> |
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<indexterm zone="extend"> |
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<primary>extending SQL</primary> |
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</indexterm> |
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<para> |
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In the sections that follow, we will discuss how you |
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can extend the <productname>PostgreSQL</productname> |
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@ -75,6 +79,15 @@ $Header: /cvsroot/pgsql/doc/src/sgml/extend.sgml,v 1.17 2002/09/21 18:32:53 pete |
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<sect1 id="type-system"> |
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<title>The <productname>PostgreSQL</productname> Type System</title> |
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<indexterm zone="type-system"> |
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<primary>extending SQL</primary> |
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<secondary>types</secondary> |
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</indexterm> |
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<indexterm zone="type-system"> |
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<primary>data types</primary> |
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</indexterm> |
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<para> |
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The <productname>PostgreSQL</productname> type system |
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can be broken down in several ways. |
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@ -109,6 +122,10 @@ $Header: /cvsroot/pgsql/doc/src/sgml/extend.sgml,v 1.17 2002/09/21 18:32:53 pete |
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<sect1 id="pg-system-catalogs"> |
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<title>About the <productname>PostgreSQL</productname> System Catalogs</title> |
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<indexterm zone="pg-system-catalogs"> |
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<primary>catalogs</primary> |
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</indexterm> |
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<para> |
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Having introduced the basic extensibility concepts, we |
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can now take a look at how the catalogs are actually |
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