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</indexterm>

<para>

The catalog <structname>pg_statistic</structname> stores statistical data

about the contents of the database. Entries are created by

<command>ANALYZE</command> and subsequently used by the query planner.

There is one entry for each table column that has been analyzed.

Note that all the statistical data is inherently approximate,

even assuming that it is up-to-date.

The catalog <structname>pg_statistic</structname> stores

statistical data about the contents of the database. Entries are

created by <xref linkend="sql-analyze" endterm="sql-analyze-title">

and subsequently used by the query planner. There is one entry for

each table column that has been analyzed. Note that all the

statistical data is inherently approximate, even assuming that it

is up-to-date.

</para>

<para>

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<term><replaceable class="PARAMETER">new_name</replaceable></term>

<listitem>

<para>

New name for the index.

The new name for the index.

</para>

</listitem>

</varlistentry>

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<refsynopsisdiv>

<synopsis>

ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ (<replaceable class="PARAMETER">column</replaceable> [, ...] ) ] ]

ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ (<replaceable class="PARAMETER">column</replaceable> [, ...] ) ] ]

</synopsis>

</refsynopsisdiv>

<para>

<command>ANALYZE</command> collects statistics about the contents

of tables in the database, and stores the results in the system

table <literal>pg_statistic</literal>. Subsequently, the query

planner uses these statistics to help determine the most efficient

execution plans for queries.

of tables in the database, and stores the results in the <link

linkend="catalog-pg-statistic"><structname>pg_statistic</></>

system catalog. Subsequently, the query planner uses these

statistics to help determine the most efficient execution plans for

queries.

</para>

<para>

will change slightly each time <command>ANALYZE</command> is run,

even if the actual table contents did not change. This might result

in small changes in the planner's estimated costs shown by

<command>EXPLAIN</command>. In rare situations, this

<xref linkend="sql-explain" endterm="sql-explain-title">. In rare situations, this

non-determinism will cause the query optimizer to choose a

different query plan between runs of <command>ANALYZE</command>. To

avoid this, raise the amount of statistics collected by

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</para>

<para>

You can see all available cursors by querying the

<structname>pg_cursors</structname> system view.

You can see all available cursors by querying the <link

linkend="view-pg-cursors"><structname>pg_cursors</></> system view.

</para>

</refsect1>

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<title>Description</title>

<para>

<command>DROP AGGREGATE</command>will delete an existing

<command>DROP AGGREGATE</command>removes an existing

aggregate function. To execute this command the current

user must be the owner of the aggregate function.

</para>

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<refsynopsisdiv>

<synopsis>

DROP DOMAIN [IF EXISTS ] <replaceable class="PARAMETER">name</replaceable> [, ...] [ CASCADE | RESTRICT ]

DROP DOMAIN [IF EXISTS ] <replaceable class="PARAMETER">name</replaceable> [, ...] [ CASCADE | RESTRICT ]

</synopsis>

</refsynopsisdiv>

<refsect1>

<title>Description</title>

<para>

<command>DROP DOMAIN</command>will removea domain. Only the

owner ofa domain can remove it.

<command>DROP DOMAIN</command>removesa domain. Only the owner of

a domain can remove it.

</para>

</refsect1>

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<title>Description</title>

<para>

<command>DROP LANGUAGE</command> will remove the definition

of the previously registered procedural language called

<replaceable class="parameter">name</replaceable>.

You must be superuser or owner of the language to

use <command>DROP LANGUAGE</command>.

<command>DROP LANGUAGE</command> removes the definition of a

previously registered procedural language. You must be a superuser

or the owner of the language to use <command>DROP LANGUAGE</>.

</para>

</refsect1>

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<title>Description</title>

<para>

<command>DROP SEQUENCE</command> removes sequence number generators.

<command>DROP SEQUENCE</command> removes sequence number

generators. A sequence can only be dropped by its owner or a superuser.

</para>

</refsect1>

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<para>

<command>DROP TABLE</command> removes tables from the database.

Only its owner candestroy a table. To empty a table of rows

Only its owner candrop a table. To empty a table of rows

without destroying the table, use <xref linkend="sql-delete"

endterm="sql-delete-title"> or <xref linkend="sql-truncate"

endterm="sql-truncate-title">.

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<title>Description</title>

<para>

<command>DROP TRIGGER</command>will remove an existing

<command>DROP TRIGGER</command>removes an existing

trigger definition. To execute this command, the current

user must be the owner of the table for which the trigger is defined.

</para>