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Don't use SGML empty tags

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For DocBook XML compatibility, don't use SGML empty tags (</>) anymore,
replace by the full tag name.  Add a warning option to catch future
occurrences.

Alexander Lakhin, Jürgen Purtz
This commit is contained in:
Peter Eisentraut
2017-10-08 21:44:17 -04:00
parent 6ecabead4b
commit c29c578908
337 changed files with 31636 additions and 31635 deletions
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140
doc/src/sgml/ref/create_view.sgml
View File

@@ -48,7 +48,7 @@ CREATE [ OR REPLACE ] [ TEMP | TEMPORARY ] [ RECURSIVE ] VIEW <replaceable class
<para>
If a schema name is given (for example, <literal>CREATE VIEW
myschema.myview ...</>) then the view is created in the specified
myschema.myview ...</literal>) then the view is created in the specified
schema. Otherwise it is created in the current schema. Temporary
views exist in a special schema, so a schema name cannot be given
when creating a temporary view. The name of the view must be
@@ -62,7 +62,7 @@ CREATE [ OR REPLACE ] [ TEMP | TEMPORARY ] [ RECURSIVE ] VIEW <replaceable class
<variablelist>
<varlistentry>
<term><literal>TEMPORARY</> or <literal>TEMP</></term>
<term><literal>TEMPORARY</literal> or <literal>TEMP</literal></term>
<listitem>
<para>
If specified, the view is created as a temporary view.
@@ -82,16 +82,16 @@ CREATE [ OR REPLACE ] [ TEMP | TEMPORARY ] [ RECURSIVE ] VIEW <replaceable class
</varlistentry>
<varlistentry>
<term><literal>RECURSIVE</></term>
<term><literal>RECURSIVE</literal></term>
<listitem>
<para>
Creates a recursive view. The syntax
<synopsis>
CREATE RECURSIVE VIEW [ <replaceable>schema</> . ] <replaceable>view_name</> (<replaceable>column_names</>) AS SELECT <replaceable>...</>;
CREATE RECURSIVE VIEW [ <replaceable>schema</replaceable> . ] <replaceable>view_name</replaceable> (<replaceable>column_names</replaceable>) AS SELECT <replaceable>...</replaceable>;
</synopsis>
is equivalent to
<synopsis>
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</>;
CREATE VIEW [ <replaceable>schema</replaceable> . ] <replaceable>view_name</replaceable> AS WITH RECURSIVE <replaceable>view_name</replaceable> (<replaceable>column_names</replaceable>) AS (SELECT <replaceable>...</replaceable>) SELECT <replaceable>column_names</replaceable> FROM <replaceable>view_name</replaceable>;
</synopsis>
A view column name list must be specified for a recursive view.
</para>
@@ -129,9 +129,9 @@ CREATE VIEW [ <replaceable>schema</> . ] <replaceable>view_name</> AS WITH RECUR
<term><literal>check_option</literal> (<type>string</type>)</term>
<listitem>
<para>
This parameter may be either <literal>local</> or
<literal>cascaded</>, and is equivalent to specifying
<literal>WITH [ CASCADED | LOCAL ] CHECK OPTION</> (see below).
This parameter may be either <literal>local</literal> or
<literal>cascaded</literal>, and is equivalent to specifying
<literal>WITH [ CASCADED | LOCAL ] CHECK OPTION</literal> (see below).
This option can be changed on existing views using <xref
linkend="sql-alterview">.
</para>
@@ -175,12 +175,12 @@ CREATE VIEW [ <replaceable>schema</> . ] <replaceable>view_name</> AS WITH RECUR
<listitem>
<para>
This option controls the behavior of automatically updatable views. When
this option is specified, <command>INSERT</> and <command>UPDATE</>
this option is specified, <command>INSERT</command> and <command>UPDATE</command>
commands on the view will be checked to ensure that new rows satisfy the
view-defining condition (that is, the new rows are checked to ensure that
they are visible through the view). If they are not, the update will be
rejected. If the <literal>CHECK OPTION</> is not specified,
<command>INSERT</> and <command>UPDATE</> commands on the view are
rejected. If the <literal>CHECK OPTION</literal> is not specified,
<command>INSERT</command> and <command>UPDATE</command> commands on the view are
allowed to create rows that are not visible through the view. The
following check options are supported:
@@ -191,7 +191,7 @@ CREATE VIEW [ <replaceable>schema</> . ] <replaceable>view_name</> AS WITH RECUR
<para>
New rows are only checked against the conditions defined directly in
the view itself. Any conditions defined on underlying base views are
not checked (unless they also specify the <literal>CHECK OPTION</>).
not checked (unless they also specify the <literal>CHECK OPTION</literal>).
</para>
</listitem>
</varlistentry>
@@ -201,9 +201,9 @@ CREATE VIEW [ <replaceable>schema</> . ] <replaceable>view_name</> AS WITH RECUR
<listitem>
<para>
New rows are checked against the conditions of the view and all
underlying base views. If the <literal>CHECK OPTION</> is specified,
and neither <literal>LOCAL</> nor <literal>CASCADED</> is specified,
then <literal>CASCADED</> is assumed.
underlying base views. If the <literal>CHECK OPTION</literal> is specified,
and neither <literal>LOCAL</literal> nor <literal>CASCADED</literal> is specified,
then <literal>CASCADED</literal> is assumed.
</para>
</listitem>
</varlistentry>
@@ -211,26 +211,26 @@ CREATE VIEW [ <replaceable>schema</> . ] <replaceable>view_name</> AS WITH RECUR
</para>
<para>
The <literal>CHECK OPTION</> may not be used with <literal>RECURSIVE</>
The <literal>CHECK OPTION</literal> may not be used with <literal>RECURSIVE</literal>
views.
</para>
<para>
Note that the <literal>CHECK OPTION</> is only supported on views that
are automatically updatable, and do not have <literal>INSTEAD OF</>
triggers or <literal>INSTEAD</> rules. If an automatically updatable
view is defined on top of a base view that has <literal>INSTEAD OF</>
triggers, then the <literal>LOCAL CHECK OPTION</> may be used to check
Note that the <literal>CHECK OPTION</literal> is only supported on views that
are automatically updatable, and do not have <literal>INSTEAD OF</literal>
triggers or <literal>INSTEAD</literal> rules. If an automatically updatable
view is defined on top of a base view that has <literal>INSTEAD OF</literal>
triggers, then the <literal>LOCAL CHECK OPTION</literal> may be used to check
the conditions on the automatically updatable view, but the conditions
on the base view with <literal>INSTEAD OF</> triggers will not be
on the base view with <literal>INSTEAD OF</literal> triggers will not be
checked (a cascaded check option will not cascade down to a
trigger-updatable view, and any check options defined directly on a
trigger-updatable view will be ignored). If the view or any of its base
relations has an <literal>INSTEAD</> rule that causes the
<command>INSERT</> or <command>UPDATE</> command to be rewritten, then
relations has an <literal>INSTEAD</literal> rule that causes the
<command>INSERT</command> or <command>UPDATE</command> command to be rewritten, then
all check options will be ignored in the rewritten query, including any
checks from automatically updatable views defined on top of the relation
with the <literal>INSTEAD</> rule.
with the <literal>INSTEAD</literal> rule.
</para>
</listitem>
</varlistentry>
@@ -251,8 +251,8 @@ CREATE VIEW [ <replaceable>schema</> . ] <replaceable>view_name</> AS WITH RECUR
<programlisting>
CREATE VIEW vista AS SELECT 'Hello World';
</programlisting>
is bad form because the column name defaults to <literal>?column?</>;
also, the column data type defaults to <type>text</>, which might not
is bad form because the column name defaults to <literal>?column?</literal>;
also, the column data type defaults to <type>text</type>, which might not
be what you wanted. Better style for a string literal in a view's
result is something like:
<programlisting>
@@ -271,7 +271,7 @@ CREATE VIEW vista AS SELECT text 'Hello World' AS hello;
</para>
<para>
When <command>CREATE OR REPLACE VIEW</> is used on an
When <command>CREATE OR REPLACE VIEW</command> is used on an
existing view, only the view's defining SELECT rule is changed.
Other view properties, including ownership, permissions, and non-SELECT
rules, remain unchanged. You must own the view
@@ -287,30 +287,30 @@ CREATE VIEW vista AS SELECT text 'Hello World' AS hello;
<para>
Simple views are automatically updatable: the system will allow
<command>INSERT</>, <command>UPDATE</> and <command>DELETE</> statements
<command>INSERT</command>, <command>UPDATE</command> and <command>DELETE</command> statements
to be used on the view in the same way as on a regular table. A view is
automatically updatable if it satisfies all of the following conditions:
<itemizedlist>
<listitem>
<para>
The view must have exactly one entry in its <literal>FROM</> list,
The view must have exactly one entry in its <literal>FROM</literal> list,
which must be a table or another updatable view.
</para>
</listitem>
<listitem>
<para>
The view definition must not contain <literal>WITH</>,
<literal>DISTINCT</>, <literal>GROUP BY</>, <literal>HAVING</>,
<literal>LIMIT</>, or <literal>OFFSET</> clauses at the top level.
The view definition must not contain <literal>WITH</literal>,
<literal>DISTINCT</literal>, <literal>GROUP BY</literal>, <literal>HAVING</literal>,
<literal>LIMIT</literal>, or <literal>OFFSET</literal> clauses at the top level.
</para>
</listitem>
<listitem>
<para>
The view definition must not contain set operations (<literal>UNION</>,
<literal>INTERSECT</> or <literal>EXCEPT</>) at the top level.
The view definition must not contain set operations (<literal>UNION</literal>,
<literal>INTERSECT</literal> or <literal>EXCEPT</literal>) at the top level.
</para>
</listitem>
@@ -327,42 +327,42 @@ CREATE VIEW vista AS SELECT text 'Hello World' AS hello;
An automatically updatable view may contain a mix of updatable and
non-updatable columns. A column is updatable if it is a simple reference
to an updatable column of the underlying base relation; otherwise the
column is read-only, and an error will be raised if an <command>INSERT</>
or <command>UPDATE</> statement attempts to assign a value to it.
column is read-only, and an error will be raised if an <command>INSERT</command>
or <command>UPDATE</command> statement attempts to assign a value to it.
</para>
<para>
If the view is automatically updatable the system will convert any
<command>INSERT</>, <command>UPDATE</> or <command>DELETE</> statement
<command>INSERT</command>, <command>UPDATE</command> or <command>DELETE</command> statement
on the view into the corresponding statement on the underlying base
relation. <command>INSERT</> statements that have an <literal>ON
CONFLICT UPDATE</> clause are fully supported.
relation. <command>INSERT</command> statements that have an <literal>ON
CONFLICT UPDATE</literal> clause are fully supported.
</para>
<para>
If an automatically updatable view contains a <literal>WHERE</>
If an automatically updatable view contains a <literal>WHERE</literal>
condition, the condition restricts which rows of the base relation are
available to be modified by <command>UPDATE</> and <command>DELETE</>
statements on the view. However, an <command>UPDATE</> is allowed to
change a row so that it no longer satisfies the <literal>WHERE</>
available to be modified by <command>UPDATE</command> and <command>DELETE</command>
statements on the view. However, an <command>UPDATE</command> is allowed to
change a row so that it no longer satisfies the <literal>WHERE</literal>
condition, and thus is no longer visible through the view. Similarly,
an <command>INSERT</> command can potentially insert base-relation rows
that do not satisfy the <literal>WHERE</> condition and thus are not
visible through the view (<literal>ON CONFLICT UPDATE</> may
an <command>INSERT</command> command can potentially insert base-relation rows
that do not satisfy the <literal>WHERE</literal> condition and thus are not
visible through the view (<literal>ON CONFLICT UPDATE</literal> may
similarly affect an existing row not visible through the view).
The <literal>CHECK OPTION</> may be used to prevent
<command>INSERT</> and <command>UPDATE</> commands from creating
The <literal>CHECK OPTION</literal> may be used to prevent
<command>INSERT</command> and <command>UPDATE</command> commands from creating
such rows that are not visible through the view.
</para>
<para>
If an automatically updatable view is marked with the
<literal>security_barrier</> property then all the view's <literal>WHERE</>
<literal>security_barrier</literal> property then all the view's <literal>WHERE</literal>
conditions (and any conditions using operators which are marked as <literal>LEAKPROOF</literal>)
will always be evaluated before any conditions that a user of the view has
added. See <xref linkend="rules-privileges"> for full details. Note that,
due to this, rows which are not ultimately returned (because they do not
pass the user's <literal>WHERE</> conditions) may still end up being locked.
pass the user's <literal>WHERE</literal> conditions) may still end up being locked.
<command>EXPLAIN</command> can be used to see which conditions are
applied at the relation level (and therefore do not lock rows) and which are
not.
@@ -372,7 +372,7 @@ CREATE VIEW vista AS SELECT text 'Hello World' AS hello;
A more complex view that does not satisfy all these conditions is
read-only by default: the system will not allow an insert, update, or
delete on the view. You can get the effect of an updatable view by
creating <literal>INSTEAD OF</> triggers on the view, which must
creating <literal>INSTEAD OF</literal> triggers on the view, which must
convert attempted inserts, etc. on the view into appropriate actions
on other tables. For more information see <xref
linkend="sql-createtrigger">. Another possibility is to create rules
@@ -404,13 +404,13 @@ CREATE VIEW comedies AS
WHERE kind = 'Comedy';
</programlisting>
This will create a view containing the columns that are in the
<literal>film</> table at the time of view creation. Though
<literal>*</> was used to create the view, columns added later to
<literal>film</literal> table at the time of view creation. Though
<literal>*</literal> was used to create the view, columns added later to
the table will not be part of the view.
</para>
<para>
Create a view with <literal>LOCAL CHECK OPTION</>:
Create a view with <literal>LOCAL CHECK OPTION</literal>:
<programlisting>
CREATE VIEW universal_comedies AS
@@ -419,16 +419,16 @@ CREATE VIEW universal_comedies AS
WHERE classification = 'U'
WITH LOCAL CHECK OPTION;
</programlisting>
This will create a view based on the <literal>comedies</> view, showing
only films with <literal>kind = 'Comedy'</> and
<literal>classification = 'U'</>. Any attempt to <command>INSERT</> or
<command>UPDATE</> a row in the view will be rejected if the new row
doesn't have <literal>classification = 'U'</>, but the film
<literal>kind</> will not be checked.
This will create a view based on the <literal>comedies</literal> view, showing
only films with <literal>kind = 'Comedy'</literal> and
<literal>classification = 'U'</literal>. Any attempt to <command>INSERT</command> or
<command>UPDATE</command> a row in the view will be rejected if the new row
doesn't have <literal>classification = 'U'</literal>, but the film
<literal>kind</literal> will not be checked.
</para>
<para>
Create a view with <literal>CASCADED CHECK OPTION</>:
Create a view with <literal>CASCADED CHECK OPTION</literal>:
<programlisting>
CREATE VIEW pg_comedies AS
@@ -437,8 +437,8 @@ CREATE VIEW pg_comedies AS
WHERE classification = 'PG'
WITH CASCADED CHECK OPTION;
</programlisting>
This will create a view that checks both the <literal>kind</> and
<literal>classification</> of new rows.
This will create a view that checks both the <literal>kind</literal> and
<literal>classification</literal> of new rows.
</para>
<para>
@@ -454,10 +454,10 @@ CREATE VIEW comedies AS
FROM films f
WHERE f.kind = 'Comedy';
</programlisting>
This view will support <command>INSERT</>, <command>UPDATE</> and
<command>DELETE</>. All the columns from the <literal>films</> table will
be updatable, whereas the computed columns <literal>country</> and
<literal>avg_rating</> will be read-only.
This view will support <command>INSERT</command>, <command>UPDATE</command> and
<command>DELETE</command>. All the columns from the <literal>films</literal> table will
be updatable, whereas the computed columns <literal>country</literal> and
<literal>avg_rating</literal> will be read-only.
</para>
<para>
@@ -469,7 +469,7 @@ UNION ALL
SELECT n+1 FROM nums_1_100 WHERE n &lt; 100;
</programlisting>
Notice that although the recursive view's name is schema-qualified in this
<command>CREATE</>, its internal self-reference is not schema-qualified.
<command>CREATE</command>, its internal self-reference is not schema-qualified.
This is because the implicitly-created CTE's name cannot be
schema-qualified.
</para>
@@ -482,7 +482,7 @@ UNION ALL
<command>CREATE OR REPLACE VIEW</command> is a
<productname>PostgreSQL</productname> language extension.
So is the concept of a temporary view.
The <literal>WITH ( ... )</> clause is an extension as well.
The <literal>WITH ( ... )</literal> clause is an extension as well.
</para>
</refsect1>