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Improve documentation for CREATE RECURSIVE VIEW. 

It was perhaps not entirely clear that internal self-references shouldn't
be schema-qualified even if the view name is written with a schema.
Spell it out.

Discussion: <871sznz69m.fsf@metapensiero.it>
This commit is contained in:
Tom Lane 2016-10-11 10:08:45 -04:00
parent 3d21f08bcc
commit e34318725c
1 changed files with 10 additions and 5 deletions
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15
doc/src/sgml/ref/create_view.sgml
View File

@ -87,13 +87,13 @@ CREATE [ OR REPLACE ] [ TEMP | TEMPORARY ] [ RECURSIVE ] VIEW <replaceable class
<para>
Creates a recursive view. The syntax
<synopsis>
CREATE RECURSIVE VIEW <replaceable>name</> (<replaceable>columns</>) AS SELECT <replaceable>...</>;
CREATE RECURSIVE VIEW [ <replaceable>schema</> . ] <replaceable>view_name</> (<replaceable>column_names</>) AS SELECT <replaceable>...</>;
</synopsis>
is equivalent to
<synopsis>
CREATE VIEW <replaceable>name</> AS WITH RECURSIVE <replaceable>name</> (<replaceable>columns</>) AS (SELECT <replaceable>...</>) SELECT <replaceable>columns</> FROM <replaceable>name</>;
CREATE VIEW [ <replaceable>schema</> . ] <replaceable>view_name</> AS WITH RECURSIVE <replaceable>view_name</> (<replaceable>column_names</>) AS (SELECT <replaceable>...</>) SELECT <replaceable>column_names</> FROM <replaceable>view_name</>;
</synopsis>
A view column list must be specified for a recursive view.
A view column name list must be specified for a recursive view.
</para>
</listitem>
</varlistentry>
@ -462,11 +462,16 @@ CREATE VIEW comedies AS
<para>
Create a recursive view consisting of the numbers from 1 to 100:
<programlisting>
CREATE RECURSIVE VIEW nums_1_100 (n) AS
CREATE RECURSIVE VIEW public.nums_1_100 (n) AS
VALUES (1)
UNION ALL
SELECT n+1 FROM nums_1_100 WHERE n < 100;
</programlisting></para>
</programlisting>
Notice that although the recursive view's name is schema-qualified in this
<command>CREATE</>, its internal self-reference is not schema-qualified.
This is because the implicitly-created CTE's name cannot be
schema-qualified.
</para>
</refsect1>
<refsect1>