diff options
| author | Magnus Hagander | 2021-03-06 16:36:48 +0000 |
|---|---|---|
| committer | Magnus Hagander | 2021-03-06 16:36:48 +0000 |
| commit | e045565dae4b2368ba812d60ef0fb7f927fe2646 (patch) | |
| tree | 75bd1c726f460128fe96e2eb48e4167de8ecd082 | |
| parent | f1516ad7b3a9645a316846fa7b2229163bc55907 (diff) | |
Improve docs on updatable views
Introduce the options before going into details, and add a link to the
CREATE TRIGGER documentation.
Author: David Johnston
Reviewed-By: Anastasia Lubennikova
Discussion: https://postgr.es/m/CAKFQuwYLLRhheo0_Y4Jp=vJ_YDsz1KoRuTpX1A_bUxmHTmLe-A@mail.gmail.com
| -rw-r--r-- | doc/src/sgml/rules.sgml | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/doc/src/sgml/rules.sgml b/doc/src/sgml/rules.sgml index aa172d102b..b017d3122e 100644 --- a/doc/src/sgml/rules.sgml +++ b/doc/src/sgml/rules.sgml @@ -797,6 +797,10 @@ SELECT t1.a, t2.b, t1.ctid FROM t1, t2 WHERE t1.a = t2.a; relation points at a subquery range-table entry, which will not work. There are several ways in which <productname>PostgreSQL</productname> can support the appearance of updating a view, however. + In order of user-experienced complexity those are: automatically substitute + in the underlying table for the view, execute a user-defined trigger, + or rewrite the query per a user-defined rule. + These options are discussed below. </para> <para> @@ -812,7 +816,8 @@ SELECT t1.a, t2.b, t1.ctid FROM t1, t2 WHERE t1.a = t2.a; <para> Alternatively, the operation may be handled by a user-provided - <literal>INSTEAD OF</literal> trigger on the view. + <literal>INSTEAD OF</literal> trigger on the view + (see <xref linkend="sql-createtrigger"/>). Rewriting works slightly differently in this case. For <command>INSERT</command>, the rewriter does nothing at all with the view, leaving it as the result relation |