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-rw-r--r--doc/src/sgml/catalogs.sgml3
-rw-r--r--doc/src/sgml/indexam.sgml11
-rw-r--r--doc/src/sgml/ref/create_table.sgml21
-rw-r--r--doc/src/sgml/ref/create_table_as.sgml12
-rw-r--r--doc/src/sgml/ref/pg_dump.sgml11
-rw-r--r--doc/src/sgml/ref/pg_dumpall.sgml11
-rw-r--r--doc/src/sgml/storage.sgml22
7 files changed, 86 insertions, 5 deletions
diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml
index 9fa20cfeee9..0eeb499207e 100644
--- a/doc/src/sgml/catalogs.sgml
+++ b/doc/src/sgml/catalogs.sgml
@@ -1644,7 +1644,8 @@
<entry><type>bool</type></entry>
<entry></entry>
<entry>
- <literal>p</> = permanent table, <literal>t</> = temporary table
+ <literal>p</> = permanent table, <literal>u</> = unlogged table,
+ <literal>t</> = temporary table
</entry>
</row>
diff --git a/doc/src/sgml/indexam.sgml b/doc/src/sgml/indexam.sgml
index c4eb59f7be7..51e70e92006 100644
--- a/doc/src/sgml/indexam.sgml
+++ b/doc/src/sgml/indexam.sgml
@@ -167,6 +167,17 @@ ambuild (Relation heapRelation,
<para>
<programlisting>
+void
+ambuildempty (Relation indexRelation);
+</programlisting>
+ Build an empty index, and write it to the initialization fork (INIT_FORKNUM)
+ of the given relation. This method is called only for unlogged tables; the
+ empty index written to the initialization fork will be copied over the main
+ relation fork on each server restart.
+ </para>
+
+ <para>
+<programlisting>
bool
aminsert (Relation indexRelation,
Datum *values,
diff --git a/doc/src/sgml/ref/create_table.sgml b/doc/src/sgml/ref/create_table.sgml
index bc5dff03296..efb4b1aca18 100644
--- a/doc/src/sgml/ref/create_table.sgml
+++ b/doc/src/sgml/ref/create_table.sgml
@@ -21,7 +21,7 @@ PostgreSQL documentation
<refsynopsisdiv>
<synopsis>
-CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } ] TABLE [ IF NOT EXISTS ] <replaceable class="PARAMETER">table_name</replaceable> ( [
+CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXISTS ] <replaceable class="PARAMETER">table_name</replaceable> ( [
{ <replaceable class="PARAMETER">column_name</replaceable> <replaceable class="PARAMETER">data_type</replaceable> [ <replaceable class="PARAMETER">column_constraint</replaceable> [ ... ] ]
| <replaceable>table_constraint</replaceable>
| LIKE <replaceable>parent_table</replaceable> [ <replaceable>like_option</replaceable> ... ] }
@@ -32,7 +32,7 @@ CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } ] TABLE [ IF NOT EXISTS ] <repl
[ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ]
[ TABLESPACE <replaceable class="PARAMETER">tablespace</replaceable> ]
-CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } ] TABLE [ IF NOT EXISTS ] <replaceable class="PARAMETER">table_name</replaceable>
+CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXISTS ] <replaceable class="PARAMETER">table_name</replaceable>
OF <replaceable class="PARAMETER">type_name</replaceable> [ (
{ <replaceable class="PARAMETER">column_name</replaceable> WITH OPTIONS [ <replaceable class="PARAMETER">column_constraint</replaceable> [ ... ] ]
| <replaceable>table_constraint</replaceable> }
@@ -165,6 +165,23 @@ CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } ] TABLE [ IF NOT EXISTS ] <repl
</varlistentry>
<varlistentry>
+ <term><literal>UNLOGGED</></term>
+ <listitem>
+ <para>
+ If specified, the table is created as an unlogged table. Data written
+ to unlogged tables is not written to the write-ahead log (see <xref
+ linkend="wal">), which makes them considerably faster than ordinary
+ tables. However, they are not crash-safe: an unlogged table is
+ automatically truncated after a crash or unclean shutdown. The contents
+ of an unlogged table are also not replicated to standby servers.
+ Any indexes created on an unlogged table are automatically unlogged as
+ well; however, unlogged <link linkend="GiST">GiST indexes</link> are
+ currently not supported and cannot be created on an unlogged table.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
<term><literal>IF NOT EXISTS</></term>
<listitem>
<para>
diff --git a/doc/src/sgml/ref/create_table_as.sgml b/doc/src/sgml/ref/create_table_as.sgml
index 3a256d1aaed..ff71078d1e2 100644
--- a/doc/src/sgml/ref/create_table_as.sgml
+++ b/doc/src/sgml/ref/create_table_as.sgml
@@ -21,7 +21,7 @@ PostgreSQL documentation
<refsynopsisdiv>
<synopsis>
-CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } ] TABLE <replaceable>table_name</replaceable>
+CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE <replaceable>table_name</replaceable>
[ (<replaceable>column_name</replaceable> [, ...] ) ]
[ WITH ( <replaceable class="PARAMETER">storage_parameter</replaceable> [= <replaceable class="PARAMETER">value</replaceable>] [, ... ] ) | WITH OIDS | WITHOUT OIDS ]
[ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ]
@@ -82,6 +82,16 @@ CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } ] TABLE <replaceable>table_name
</varlistentry>
<varlistentry>
+ <term><literal>UNLOGGED</></term>
+ <listitem>
+ <para>
+ If specified, the table is created as an unlogged table.
+ Refer to <xref linkend="sql-createtable"> for details.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
<term><replaceable>table_name</replaceable></term>
<listitem>
<para>
diff --git a/doc/src/sgml/ref/pg_dump.sgml b/doc/src/sgml/ref/pg_dump.sgml
index fd13c0d9e75..b291a257ea7 100644
--- a/doc/src/sgml/ref/pg_dump.sgml
+++ b/doc/src/sgml/ref/pg_dump.sgml
@@ -670,6 +670,17 @@ PostgreSQL documentation
</varlistentry>
<varlistentry>
+ <term><option>--no-unlogged-table-data</option></term>
+ <listitem>
+ <para>
+ Do not dump the contents of unlogged tables. This option has no
+ effect on whether or not the table definitions (schema) are dumped;
+ it only suppresses dumping the table data.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
<term><option>--quote-all-identifiers</></term>
<listitem>
<para>
diff --git a/doc/src/sgml/ref/pg_dumpall.sgml b/doc/src/sgml/ref/pg_dumpall.sgml
index 39da0b29490..04e95e876d1 100644
--- a/doc/src/sgml/ref/pg_dumpall.sgml
+++ b/doc/src/sgml/ref/pg_dumpall.sgml
@@ -202,6 +202,17 @@ PostgreSQL documentation
</varlistentry>
<varlistentry>
+ <term><option>--no-unlogged-table-data</option></term>
+ <listitem>
+ <para>
+ Do not dump the contents of unlogged tables. This option has no
+ effect on whether or not the table definitions (schema) are dumped;
+ it only suppresses dumping the table data.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
<term><option>-r</option></term>
<term><option>--roles-only</option></term>
<listitem>
diff --git a/doc/src/sgml/storage.sgml b/doc/src/sgml/storage.sgml
index cda7f6452f5..430df4a8438 100644
--- a/doc/src/sgml/storage.sgml
+++ b/doc/src/sgml/storage.sgml
@@ -147,7 +147,9 @@ the relation. The free space map is stored in a file named with the filenode
number plus the suffix <literal>_fsm</>. Tables also have a
<firstterm>visibility map</>, stored in a fork with the suffix <literal>_vm</>,
to track which pages are known to have no dead tuples. The visibility map is
-described further in <xref linkend="storage-vm">.
+described further in <xref linkend="storage-vm">. Unlogged tables and indexes
+have a third fork, known as the initialization fork, which is stored in a fork
+with the suffix <literal>_init</literal> (see <xref linkend="storage-init">).
</para>
<caution>
@@ -485,6 +487,24 @@ a bit is not set, it might or might not be true.
</sect1>
+<sect1 id="storage-init">
+
+<title>The Initialization Fork</title>
+
+<indexterm>
+ <primary>Initialization Fork</primary>
+</indexterm>
+
+<para>
+Each unlogged table, and each index on an unlogged table, has an initialization
+fork. The initialization fork is an empty table or index of the appropriate
+type. When an unlogged table must be reset to empty due to a crash, the
+initialization fork is copied over the main fork, and any other forks are
+erased (they will be recreated automatically as needed).
+</para>
+
+</sect1>
+
<sect1 id="storage-page-layout">
<title>Database Page Layout</title>
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-08 08:40:56 +0000