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| author | Alvaro Herrera <alvherre@alvh.no-ip.org> | 2020-10-27 13:49:19 -0300 |
|---|---|---|
| committer | Alvaro Herrera <alvherre@alvh.no-ip.org> | 2020-10-27 13:49:19 -0300 |
| commit | 59ab4ac32460a6a93b665f4e487d7ff64979ba4d (patch) | |
| tree | d785935ff51d919383cc2d51ecd2dd13d37dcd94 /doc/src | |
| parent | 4066b642909176aede03b6c64d29734ce2a34716 (diff) | |
| download | postgresql-59ab4ac32460a6a93b665f4e487d7ff64979ba4d.tar.gz postgresql-59ab4ac32460a6a93b665f4e487d7ff64979ba4d.zip | |
Accept relations of any kind in LOCK TABLE
The restriction that only tables and views can be locked by LOCK TABLE
is quite arbitrary, since the underlying mechanism can lock any relation
type. Drop the restriction so that programs such as pg_dump can lock
all relations they're interested in, preventing schema changes that
could cause a dump to fail after expending much effort.
Backpatch to 9.5.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reported-by: Wells Oliver <wells.oliver@gmail.com>
Discussion: https://postgr.es/m/20201021200659.GA32358@alvherre.pgsql
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/ref/lock.sgml | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/doc/src/sgml/ref/lock.sgml b/doc/src/sgml/ref/lock.sgml index 4cdfae2279e..37881f25ac5 100644 --- a/doc/src/sgml/ref/lock.sgml +++ b/doc/src/sgml/ref/lock.sgml @@ -16,7 +16,7 @@ PostgreSQL documentation <refnamediv> <refname>LOCK</refname> - <refpurpose>lock a table</refpurpose> + <refpurpose>lock a named relation (table, etc)</refpurpose> </refnamediv> <refsynopsisdiv> @@ -34,7 +34,9 @@ LOCK [ TABLE ] [ ONLY ] <replaceable class="parameter">name</replaceable> [ * ] <title>Description</title> <para> - <command>LOCK TABLE</command> obtains a table-level lock, waiting + <command>LOCK TABLE</command> obtains a table-level lock on a + relation (table, partitioned table, foreign table, view, + materialized view, index, composite type, sequence), waiting if necessary for any conflicting locks to be released. If <literal>NOWAIT</literal> is specified, <command>LOCK TABLE</command> does not wait to acquire the desired lock: if it @@ -115,17 +117,18 @@ LOCK [ TABLE ] [ ONLY ] <replaceable class="parameter">name</replaceable> [ * ] <term><replaceable class="parameter">name</replaceable></term> <listitem> <para> - The name (optionally schema-qualified) of an existing table to - lock. If <literal>ONLY</literal> is specified before the table name, only that + The name (optionally schema-qualified) of an existing relation to + lock. If <literal>ONLY</literal> is specified before a table name, only that table is locked. If <literal>ONLY</literal> is not specified, the table and all its descendant tables (if any) are locked. Optionally, <literal>*</literal> can be specified after the table name to explicitly indicate that - descendant tables are included. + descendant tables are included. When locking a view, all relations appearing + in the view definition are locked, regardless of <literal>ONLY</literal>. </para> <para> The command <literal>LOCK TABLE a, b;</literal> is equivalent to - <literal>LOCK TABLE a; LOCK TABLE b;</literal>. The tables are locked + <literal>LOCK TABLE a; LOCK TABLE b;</literal>. The relations are locked one-by-one in the order specified in the <command>LOCK TABLE</command> command. </para> |