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Add note about pg_stats to pg_statistic entry; add sections for
pg_largeobject, pg_listener, pg_rewrite, pg_trigger; miscellaneous small improvements.
This commit is contained in:
Tom Lane
parent
e158670c1f
commit
daf72bba91
@ -1,6 +1,6 @@
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<!--
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<!--
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Documentation of the system catalogs, directed toward PostgreSQL developers
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Documentation of the system catalogs, directed toward PostgreSQL developers
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$Header: /cvsroot/pgsql/doc/src/sgml/catalogs.sgml,v 2.25 2001/09/13 15:55:22 petere Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/catalogs.sgml,v 2.26 2001/10/15 22:47:47 tgl Exp $
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-->
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-->
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<chapter id="catalogs">
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<chapter id="catalogs">
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@ -63,7 +63,7 @@
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<row>
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<row>
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<entry>pg_attribute</entry>
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<entry>pg_attribute</entry>
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<entry>table columns (attributes, fields)</entry>
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<entry>table columns (<quote>attributes</quote>, <quote>fields</quote>)</entry>
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</row>
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</row>
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<row>
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<row>
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@ -73,7 +73,7 @@
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<row>
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<row>
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<entry>pg_database</entry>
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<entry>pg_database</entry>
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<entry>databases</entry>
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<entry>databases within this database cluster</entry>
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</row>
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</row>
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<row>
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<row>
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@ -83,7 +83,7 @@
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<row>
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<row>
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<entry>pg_group</entry>
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<entry>pg_group</entry>
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<entry>user groups</entry>
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<entry>groups of database users</entry>
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</row>
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</row>
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<row>
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<row>
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@ -162,8 +162,7 @@
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<para>
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<para>
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More detailed documentation of most catalogs follow below. The
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More detailed documentation of most catalogs follow below. The
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catalogs that relate to index access methods are explained in the
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catalogs that relate to index access methods are explained in the
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<citetitle>Programmer's Guide</citetitle>. Some catalogs don't
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<citetitle>Programmer's Guide</citetitle>.
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have any documentation, yet.
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</para>
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</para>
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</section>
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</section>
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@ -210,13 +209,13 @@
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<row>
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<row>
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<entry>aggtransfn</entry>
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<entry>aggtransfn</entry>
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<entry><type>regproc</type> (function)</entry>
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<entry><type>regproc</type> (function)</entry>
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<entry></entry>
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<entry>pg_proc.oid</entry>
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<entry>Transition function</entry>
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<entry>Transition function</entry>
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</row>
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</row>
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<row>
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<row>
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<entry>aggfinalfn</entry>
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<entry>aggfinalfn</entry>
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<entry><type>regproc</type> (function)</entry>
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<entry><type>regproc</type> (function)</entry>
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<entry></entry>
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<entry>pg_proc.oid</entry>
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<entry>Final function</entry>
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<entry>Final function</entry>
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</row>
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</row>
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<row>
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<row>
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@ -431,7 +430,7 @@
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<entry></entry>
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<entry></entry>
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<entry>
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<entry>
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Always -1 in storage, but when loaded into a tuple descriptor
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Always -1 in storage, but when loaded into a tuple descriptor
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in memory this may be updated cache the offset of the attribute
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in memory this may be updated to cache the offset of the attribute
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within the tuple.
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within the tuple.
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</entry>
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</entry>
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</row>
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</row>
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@ -653,7 +652,8 @@
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<entry><type>bool</type></entry>
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<entry><type>bool</type></entry>
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<entry></entry>
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<entry></entry>
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<entry>True if this table is shared across all databases in the
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<entry>True if this table is shared across all databases in the
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cluster.</entry>
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cluster. Only certain system catalogs (such as
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<structname>pg_database</structname>) are shared.</entry>
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</row>
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</row>
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<row>
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<row>
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@ -741,7 +741,9 @@
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<entry>relhasrules</entry>
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<entry>relhasrules</entry>
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<entry><type>bool</type></entry>
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<entry><type>bool</type></entry>
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<entry></entry>
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<entry></entry>
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<entry>Table has rules</entry>
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<entry>Table has rules; see
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<structname>pg_rewrite</structname> catalog
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</entry>
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</row>
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</row>
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<row>
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<row>
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@ -772,14 +774,19 @@
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<para>
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<para>
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The <structname>pg_database</structname> catalog stores information
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The <structname>pg_database</structname> catalog stores information
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about the available databases. The
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about the available databases. Databases are created with the
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<structname>pg_database</structname> table is shared between all
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<command>CREATE DATABASE</command> command. Consult the
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databases of a cluster. Databases are created with the
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<command>CREATE DATABASE</command>. Consult the
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<citetitle>Administrator's Guide</citetitle> for details about the
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<citetitle>Administrator's Guide</citetitle> for details about the
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meaning of some of the parameters.
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meaning of some of the parameters.
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</para>
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</para>
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<para>
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Unlike most system catalogs, <structname>pg_database</structname>
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is shared across all databases of a cluster: there is only one
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copy of <structname>pg_database</structname> per cluster, not
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one per database.
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</para>
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<table>
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<table>
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<title>pg_database Columns</title>
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<title>pg_database Columns</title>
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@ -959,6 +966,14 @@
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Guide</citetitle> for information about user permission management.
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Guide</citetitle> for information about user permission management.
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</para>
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</para>
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<para>
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Because user and group identities are cluster-wide,
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<structname>pg_group</structname>
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is shared across all databases of a cluster: there is only one
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copy of <structname>pg_group</structname> per cluster, not
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one per database.
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</para>
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<table>
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<table>
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<title>pg_group Columns</title>
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<title>pg_group Columns</title>
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@ -1039,7 +1054,7 @@
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<row>
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<row>
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<entry>indproc</entry>
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<entry>indproc</entry>
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<entry><type>oid</type></entry>
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<entry><type>regproc</type></entry>
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<entry>pg_proc.oid</entry>
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<entry>pg_proc.oid</entry>
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<entry>The registered procedure if this is a functional index</entry>
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<entry>The registered procedure if this is a functional index</entry>
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</row>
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</row>
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@ -1086,7 +1101,8 @@
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<entry>indisprimary</entry>
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<entry>indisprimary</entry>
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<entry><type>bool</type></entry>
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<entry><type>bool</type></entry>
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<entry></entry>
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<entry></entry>
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<entry>If true, this index is a unique index that represents the primary key of the table.</entry>
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<entry>If true, this index represents the primary key of the table.
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(indisunique should always be true when this is true.)</entry>
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</row>
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</row>
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<row>
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<row>
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@ -1147,7 +1163,7 @@
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<entry><type>oid</type></entry>
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<entry><type>oid</type></entry>
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<entry>pg_class.oid</entry>
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<entry>pg_class.oid</entry>
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<entry>
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<entry>
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This is the reference to the parent table, from which the table
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This is the reference to the parent table, which the table
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referenced by <structfield>inhrelid</structfield> inherited
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referenced by <structfield>inhrelid</structfield> inherited
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from.
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from.
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</entry>
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</entry>
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@ -1158,7 +1174,7 @@
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<entry><type>int4</type></entry>
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<entry><type>int4</type></entry>
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<entry></entry>
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<entry></entry>
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<entry>
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<entry>
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If there is more than one subtable/parent pair (multiple
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If there is more than one parent for a subtable (multiple
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inheritance), this number tells the order in which the
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inheritance), this number tells the order in which the
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inherited columns are to be arranged. The count starts at 1.
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inherited columns are to be arranged. The count starts at 1.
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</entry>
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</entry>
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@ -1250,6 +1266,132 @@
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</section>
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</section>
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<section id="catalog-pg-largeobject">
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<title>pg_largeobject</title>
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<para>
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<structname>pg_largeobject</structname> holds the data making up
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<quote>large objects</quote>. A large object is identified by an
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OID assigned when it is created. Each large object is broken into
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segments or <quote>pages</> small enough to be conveniently stored as rows
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in <structname>pg_largeobject</structname>.
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The amount of data per page is defined to be LOBLKSIZE (which is currently
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BLCKSZ/4, or typically 2Kbytes).
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</para>
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<table>
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<title>pg_largeobject Columns</title>
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<tgroup cols=4>
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<thead>
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<row>
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<entry>Name</entry>
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<entry>Type</entry>
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<entry>References</entry>
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<entry>Description</entry>
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</row>
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</thead>
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<tbody>
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<row>
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<entry>loid</entry>
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<entry><type>oid</type></entry>
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<entry></entry>
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<entry>Identifier of the large object that includes this page</entry>
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</row>
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<row>
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<entry>pageno</entry>
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<entry><type>int4</type></entry>
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<entry></entry>
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<entry>Page number of this page within its large object
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(counting from zero)</entry>
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</row>
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<row>
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<entry>data</entry>
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<entry><type>bytea</type></entry>
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<entry></entry>
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<entry>
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Actual data stored in the large object.
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This will never be more than LOBLKSIZE bytes, and may be less.
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</entry>
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</row>
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</tbody>
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</tgroup>
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</table>
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<para>
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Each row of <structname>pg_largeobject</structname> holds data
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for one page of a large object, beginning at
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byte offset (pageno * LOBLKSIZE) within the object. The implementation
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allows sparse storage: pages may be missing, and may be shorter than
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LOBLKSIZE bytes even if they are not the last page of the object.
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Missing regions within a large object read as zeroes.
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</para>
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</section>
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<section id="catalog-pg-listener">
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<title>pg_listener</title>
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<para>
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<structname>pg_listener</structname> supports the <command>LISTEN</>
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and <command>NOTIFY</> commands. A listener creates an entry in
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<structname>pg_listener</structname> for each notification name
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it is listening for. A notifier scans <structname>pg_listener</structname>
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and updates each matching entry to show that a notification has occurred.
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The notifier also sends a signal (using the PID recorded in the table)
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to awaken the listener from sleep.
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</para>
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<table>
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<title>pg_listener Columns</title>
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<tgroup cols=4>
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<thead>
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<row>
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<entry>Name</entry>
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<entry>Type</entry>
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<entry>References</entry>
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<entry>Description</entry>
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</row>
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</thead>
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<tbody>
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<row>
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<entry>relname</entry>
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<entry><type>name</type></entry>
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<entry></entry>
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<entry>Notify condition name. (The name need not match any actual
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relation in the database; the term <quote>relname</> is historical.)
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</entry>
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</row>
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<row>
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<entry>listenerpid</entry>
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<entry><type>int4</type></entry>
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<entry></entry>
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<entry>PID of the backend process that created this entry.</entry>
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</row>
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<row>
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<entry>notification</entry>
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<entry><type>int4</type></entry>
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<entry></entry>
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<entry>
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Zero if no event is pending for this listener. If an event is
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pending, the PID of the backend that sent the notification.
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</entry>
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</row>
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</tbody>
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</tgroup>
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</table>
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</section>
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<section id="catalog-pg-operator">
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<section id="catalog-pg-operator">
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<title>pg_operator</title>
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<title>pg_operator</title>
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@ -1489,7 +1631,8 @@
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<entry>proretset</entry>
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<entry>proretset</entry>
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<entry><type>bool</type></entry>
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<entry><type>bool</type></entry>
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<entry></entry>
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<entry></entry>
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<entry>Function returns a set (probably not functional)</entry>
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<entry>Function returns a set (ie, multiple values of the specified
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datatype)</entry>
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</row>
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</row>
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<row>
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<row>
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@ -1542,7 +1685,7 @@
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This tells the function handler how to invoke the function. It
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This tells the function handler how to invoke the function. It
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might be the actual source code of the function for interpreted
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might be the actual source code of the function for interpreted
|
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languages, a link symbol, a file name, or just about anything
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languages, a link symbol, a file name, or just about anything
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else, depending the implementation language/call convention.
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else, depending on the implementation language/call convention.
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</entry>
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</entry>
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</row>
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</row>
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@ -1550,12 +1693,26 @@
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<entry>probin</entry>
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<entry>probin</entry>
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<entry><type>bytea</type></entry>
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<entry><type>bytea</type></entry>
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<entry></entry>
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<entry></entry>
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<entry>?</entry>
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<entry>Additional information about how to invoke the function.
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Again, the interpretation is language-specific.
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</entry>
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</row>
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</row>
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</tbody>
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</tbody>
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</tgroup>
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</tgroup>
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</table>
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</table>
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<para>
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Currently, prosrc contains the function's C-language name (link symbol)
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for compiled functions, both built-in and dynamically loaded. For all
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other language types, prosrc contains the function's source text.
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</para>
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<para>
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Currently, probin is unused except for dynamically-loaded C functions,
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for which it gives the name of the shared library file containing the
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function.
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</para>
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</section>
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</section>
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@ -1608,7 +1765,7 @@
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<entry>rcsrc</entry>
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<entry>rcsrc</entry>
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<entry><type>text</type></entry>
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<entry><type>text</type></entry>
|
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<entry></entry>
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<entry></entry>
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||||||
<entry>A human-readable representation of the consraint expression</entry>
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<entry>A human-readable representation of the constraint expression</entry>
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</row>
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</row>
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</tbody>
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</tbody>
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</tgroup>
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</tgroup>
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@ -1624,6 +1781,93 @@
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</section>
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</section>
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<section id="catalog-pg-rewrite">
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<title>pg_rewrite</title>
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<para>
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This system catalog stores rewrite rules for tables and views.
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</para>
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<table>
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<title>pg_rewrite Columns</title>
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||||||
|
<tgroup cols=4>
|
||||||
|
<thead>
|
||||||
|
<row>
|
||||||
|
<entry>Name</entry>
|
||||||
|
<entry>Type</entry>
|
||||||
|
<entry>References</entry>
|
||||||
|
<entry>Description</entry>
|
||||||
|
</row>
|
||||||
|
</thead>
|
||||||
|
|
||||||
|
<tbody>
|
||||||
|
<row>
|
||||||
|
<entry>rulename</entry>
|
||||||
|
<entry><type>name</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>Rule name</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>ev_type</entry>
|
||||||
|
<entry><type>char</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>Event type that the rule is for: '1' = SELECT,
|
||||||
|
'2' = UPDATE, '3' = INSERT, '4' = DELETE</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>ev_class</entry>
|
||||||
|
<entry><type>oid</type></entry>
|
||||||
|
<entry>pg_class.oid</entry>
|
||||||
|
<entry>The table this rule is for</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>ev_attr</entry>
|
||||||
|
<entry><type>int2</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>The column this rule is for (currently, always zero to
|
||||||
|
indicate the whole table)</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>is_instead</entry>
|
||||||
|
<entry><type>bool</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>True if the rule is an INSTEAD rule</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>ev_qual</entry>
|
||||||
|
<entry><type>text</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>Expression tree (in the form of a nodeToString representation)
|
||||||
|
for the rule's qualifying condition</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>ev_action</entry>
|
||||||
|
<entry><type>text</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>Query tree (in the form of a nodeToString representation)
|
||||||
|
for the rule's action</entry>
|
||||||
|
</row>
|
||||||
|
</tbody>
|
||||||
|
</tgroup>
|
||||||
|
</table>
|
||||||
|
|
||||||
|
<note>
|
||||||
|
<para>
|
||||||
|
<structname>pg_class</structname>.<structfield>relhasrules</structfield>
|
||||||
|
must be true if a table has any rules in this catalog.
|
||||||
|
</para>
|
||||||
|
</note>
|
||||||
|
|
||||||
|
</section>
|
||||||
|
|
||||||
|
|
||||||
<section id="catalog-pg-shadow">
|
<section id="catalog-pg-shadow">
|
||||||
<title>pg_shadow</title>
|
<title>pg_shadow</title>
|
||||||
|
|
||||||
@ -1631,7 +1875,7 @@
|
|||||||
<structname>pg_shadow</structname> contains information about
|
<structname>pg_shadow</structname> contains information about
|
||||||
database users. The name stems from the fact that this table
|
database users. The name stems from the fact that this table
|
||||||
should not be readable by the public since it contains passwords.
|
should not be readable by the public since it contains passwords.
|
||||||
<structname>pg_user</structname> is a view on
|
<structname>pg_user</structname> is a publicly readable view on
|
||||||
<structname>pg_shadow</structname> that blanks out the password field.
|
<structname>pg_shadow</structname> that blanks out the password field.
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
@ -1640,6 +1884,14 @@
|
|||||||
information about user and permission management.
|
information about user and permission management.
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
|
<para>
|
||||||
|
Because user identities are cluster-wide,
|
||||||
|
<structname>pg_shadow</structname>
|
||||||
|
is shared across all databases of a cluster: there is only one
|
||||||
|
copy of <structname>pg_shadow</structname> per cluster, not
|
||||||
|
one per database.
|
||||||
|
</para>
|
||||||
|
|
||||||
<table>
|
<table>
|
||||||
<title>pg_shadow Columns</title>
|
<title>pg_shadow Columns</title>
|
||||||
|
|
||||||
@ -1743,6 +1995,20 @@
|
|||||||
<filename>src/include/catalog/pg_statistic.h</filename>.
|
<filename>src/include/catalog/pg_statistic.h</filename>.
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
|
<para>
|
||||||
|
<structname>pg_statistic</structname> should not be readable by the
|
||||||
|
public, since even statistical information about a table's contents
|
||||||
|
may be considered sensitive. (Example: minimum and maximum values
|
||||||
|
of a salary column might be quite interesting.)
|
||||||
|
<structname>pg_stats</structname> is a publicly readable view on
|
||||||
|
<structname>pg_statistic</structname> that only exposes information
|
||||||
|
about those tables that are readable by the current user.
|
||||||
|
<structname>pg_stats</structname> is also designed to present the
|
||||||
|
information in a more readable format than the underlying
|
||||||
|
<structname>pg_statistic</structname> table --- at the cost that
|
||||||
|
its schema must be extended whenever new slot types are added.
|
||||||
|
</para>
|
||||||
|
|
||||||
<table>
|
<table>
|
||||||
<title>pg_statistic Columns</title>
|
<title>pg_statistic Columns</title>
|
||||||
|
|
||||||
@ -1843,9 +2109,144 @@
|
|||||||
</section>
|
</section>
|
||||||
|
|
||||||
|
|
||||||
|
<section id="catalog-pg-trigger">
|
||||||
|
<title>pg_trigger</title>
|
||||||
|
|
||||||
|
<para>
|
||||||
|
This system catalog stores triggers on tables. See under
|
||||||
|
<command>CREATE TRIGGER</command> for more information.
|
||||||
|
</para>
|
||||||
|
|
||||||
|
<table>
|
||||||
|
<title>pg_trigger Columns</title>
|
||||||
|
|
||||||
|
<tgroup cols=4>
|
||||||
|
<thead>
|
||||||
|
<row>
|
||||||
|
<entry>Name</entry>
|
||||||
|
<entry>Type</entry>
|
||||||
|
<entry>References</entry>
|
||||||
|
<entry>Description</entry>
|
||||||
|
</row>
|
||||||
|
</thead>
|
||||||
|
|
||||||
|
<tbody>
|
||||||
|
<row>
|
||||||
|
<entry>tgrelid</entry>
|
||||||
|
<entry><type>oid</type></entry>
|
||||||
|
<entry>pg_class.oid</entry>
|
||||||
|
<entry>The table this trigger is on</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>tgname</entry>
|
||||||
|
<entry><type>name</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>Trigger name (need not be unique)</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>tgfoid</entry>
|
||||||
|
<entry><type>oid</type></entry>
|
||||||
|
<entry>pg_proc.oid</entry>
|
||||||
|
<entry>The function to be called</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>tgtype</entry>
|
||||||
|
<entry><type>int2</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>Bitmask identifying trigger conditions</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>tgenabled</entry>
|
||||||
|
<entry><type>bool</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>True if trigger is enabled (not presently checked everywhere
|
||||||
|
it should be, so disabling a trigger by setting this false does not
|
||||||
|
work reliably)</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>tgisconstraint</entry>
|
||||||
|
<entry><type>bool</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>True if trigger is a RI constraint</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>tgconstrname</entry>
|
||||||
|
<entry><type>name</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>RI constraint name</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>tgconstrrelid</entry>
|
||||||
|
<entry><type>oid</type></entry>
|
||||||
|
<entry>pg_class.oid</entry>
|
||||||
|
<entry>The table referenced by an RI constraint</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>tgdeferrable</entry>
|
||||||
|
<entry><type>bool</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>True if deferrable</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>tginitdeferred</entry>
|
||||||
|
<entry><type>bool</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>True if initially deferred</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>tgnargs</entry>
|
||||||
|
<entry><type>int2</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>Number of argument strings passed to trigger function</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>tgattr</entry>
|
||||||
|
<entry><type>int2vector</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>Currently unused</entry>
|
||||||
|
</row>
|
||||||
|
|
||||||
|
<row>
|
||||||
|
<entry>tgargs</entry>
|
||||||
|
<entry><type>bytea</type></entry>
|
||||||
|
<entry></entry>
|
||||||
|
<entry>Argument strings to pass to trigger, each null-terminated</entry>
|
||||||
|
</row>
|
||||||
|
</tbody>
|
||||||
|
</tgroup>
|
||||||
|
</table>
|
||||||
|
|
||||||
|
<note>
|
||||||
|
<para>
|
||||||
|
<structname>pg_class</structname>.<structfield>reltriggers</structfield>
|
||||||
|
needs to match up with the entries in this table.
|
||||||
|
</para>
|
||||||
|
</note>
|
||||||
|
|
||||||
|
</section>
|
||||||
|
|
||||||
|
|
||||||
<section id="catalog-pg-type">
|
<section id="catalog-pg-type">
|
||||||
<title>pg_type</title>
|
<title>pg_type</title>
|
||||||
|
|
||||||
|
<para>
|
||||||
|
This catalog stores information about datatypes. Scalar types
|
||||||
|
(<quote>base types</>) are created with <command>CREATE TYPE</command>.
|
||||||
|
A complex type is also created for each table in the database, to
|
||||||
|
represent the row structure of the table.
|
||||||
|
</para>
|
||||||
|
|
||||||
<table>
|
<table>
|
||||||
<title>pg_type Columns</title>
|
<title>pg_type Columns</title>
|
||||||
|
|
||||||
@ -1913,8 +2314,8 @@
|
|||||||
<entry></entry>
|
<entry></entry>
|
||||||
<entry>
|
<entry>
|
||||||
<structfield>typtype</structfield> is <literal>b</literal> for
|
<structfield>typtype</structfield> is <literal>b</literal> for
|
||||||
a basic type and <literal>c</literal> for a catalog type (i.e.,
|
a base type and <literal>c</literal> for a complex type (i.e.,
|
||||||
a table). If <structfield>typtype</structfield> is
|
a table's row type). If <structfield>typtype</structfield> is
|
||||||
<literal>c</literal>, <structfield>typrelid</structfield> is
|
<literal>c</literal>, <structfield>typrelid</structfield> is
|
||||||
the OID of the type's entry in
|
the OID of the type's entry in
|
||||||
<structname>pg_class</structname>.
|
<structname>pg_class</structname>.
|
||||||
@ -1925,7 +2326,10 @@
|
|||||||
<entry>typisdefined</entry>
|
<entry>typisdefined</entry>
|
||||||
<entry><type>bool</type></entry>
|
<entry><type>bool</type></entry>
|
||||||
<entry></entry>
|
<entry></entry>
|
||||||
<entry>???</entry>
|
<entry>True if the type is defined, false if this is a placeholder
|
||||||
|
entry for a not-yet-defined type. When typisdefined is false,
|
||||||
|
nothing except the type name and OID can be relied on.
|
||||||
|
</entry>
|
||||||
</row>
|
</row>
|
||||||
|
|
||||||
<row>
|
<row>
|
||||||
@ -1940,7 +2344,7 @@
|
|||||||
<entry><type>oid</type></entry>
|
<entry><type>oid</type></entry>
|
||||||
<entry>pg_class.oid</entry>
|
<entry>pg_class.oid</entry>
|
||||||
<entry>
|
<entry>
|
||||||
If this is a catalog type (see
|
If this is a complex type (see
|
||||||
<structfield>typtype</structfield>), then this field points to
|
<structfield>typtype</structfield>), then this field points to
|
||||||
the <structfield>pg_class</structfield> entry that defines the
|
the <structfield>pg_class</structfield> entry that defines the
|
||||||
corresponding table. A table could theoretically be used as a
|
corresponding table. A table could theoretically be used as a
|
||||||
|
|||||||
Loading…
x
Reference in New Issue
Block a user