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Fix markup for docbook2man man page generation.

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No big deal; fixed lots of other markup at the same time.
Bigest change: make sure there is no whitespace
 in front of <term> contents.
This will probably help the other output types too.
This commit is contained in:
Thomas G. Lockhart
1999-07-06 17:16:42 +00:00
parent 192a66e3da
commit a4ac2f458e
63 changed files with 10692 additions and 11081 deletions
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395
doc/src/sgml/ref/create_rule.sgml
View File

@@ -1,132 +1,123 @@
<REFENTRY ID="SQL-CREATERULE">
<REFMETA>
<REFENTRYTITLE>
<refentry id="SQL-CREATERULE">
<refmeta>
<refentrytitle>
CREATE RULE
</REFENTRYTITLE>
<REFMISCINFO>SQL - Language Statements</REFMISCINFO>
</REFMETA>
<REFNAMEDIV>
<REFNAME>
</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>
CREATE RULE
</REFNAME>
<REFPURPOSE>
</refname>
<refpurpose>
Defines a new rule
</REFPURPOSE>
</refpurpose>
</refnamediv>
<REFSYNOPSISDIV>
<REFSYNOPSISDIVINFO>
<DATE>1998-09-11</DATE>
</REFSYNOPSISDIVINFO>
<SYNOPSIS>
CREATE RULE <replaceable class="parameter">name</replaceable>
AS ON <replaceable class="parameter">event</replaceable>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>1998-09-11</date>
</refsynopsisdivinfo>
<synopsis>
CREATE RULE <replaceable class="parameter">name</replaceable> AS ON <replaceable class="parameter">event</replaceable>
TO <replaceable class="parameter">object</replaceable> [ WHERE <replaceable class="parameter">condition</replaceable> ]
DO [ INSTEAD ] [ <replaceable class="parameter">action</replaceable> | NOTHING ]
</SYNOPSIS>
<REFSECT2 ID="R2-SQL-CREATERULE-1">
<REFSECT2INFO>
<DATE>1998-09-11</DATE>
</REFSECT2INFO>
<TITLE>
Inputs
</TITLE>
<PARA>
</PARA>
<VARIABLELIST>
<VARLISTENTRY>
<TERM>
<replaceable class="parameter">name</replaceable>
</TERM>
<LISTITEM>
<PARA>
The name of a rule to create.
</PARA>
</LISTITEM>
</VARLISTENTRY>
<VARLISTENTRY>
<TERM>
<replaceable class="parameter">event</replaceable>
</TERM>
<LISTITEM>
<PARA>
Event is one of <literal>select</literal>,
<literal>update</literal>, <literal>delete</literal>
or <literal>insert</literal>.
</PARA>
</LISTITEM>
</VARLISTENTRY>
<VARLISTENTRY>
<TERM>
<replaceable class="parameter">object</replaceable>
</TERM>
<LISTITEM>
<PARA>
Object is either <replaceable class="parameter">table</replaceable>
or <replaceable class="parameter">table</replaceable>.<replaceable class="parameter">column</replaceable>.
</PARA>
</LISTITEM>
</VARLISTENTRY>
<VARLISTENTRY>
<TERM>
<replaceable class="parameter">condition</replaceable>
</TERM>
<LISTITEM>
<PARA>
Any SQL WHERE clause. <literal>new</literal> or
<literal>current</literal> can appear instead of an instance
variable whenever an instance variable is permissible in SQL.
</PARA>
</LISTITEM>
</VARLISTENTRY>
<VARLISTENTRY>
<TERM>
<replaceable class="parameter">action</replaceable>
</TERM>
<LISTITEM>
<PARA>
Any SQL statement. <literal>new</literal> or
<literal>current</literal> can appear instead of an instance
variable whenever an instance variable is permissible in SQL.
</PARA>
</LISTITEM>
</VARLISTENTRY>
</VARIABLELIST>
</synopsis>
</REFSECT2>
<REFSECT2 ID="R2-SQL-CREATERULE-2">
<REFSECT2INFO>
<DATE>1998-09-11</DATE>
</REFSECT2INFO>
<TITLE>
Outputs
</TITLE>
<PARA>
<VARIABLELIST>
<VARLISTENTRY>
<TERM>
<ReturnValue>CREATE</ReturnValue>
</TERM>
<LISTITEM>
<PARA>
Message returned if the rule is successfully created.
</para>
<refsect2 id="R2-SQL-CREATERULE-1">
<refsect2info>
<date>1998-09-11</date>
</refsect2info>
<title>
Inputs
</title>
<para>
<variablelist>
<varlistentry>
<term><replaceable class="parameter">name</replaceable></term>
<listitem>
<para>
The name of a rule to create.
</para>
</listitem>
</VARLISTENTRY>
</VARIABLELIST>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">event</replaceable></term>
<listitem>
<para>
Event is one of <literal>select</literal>,
<literal>update</literal>, <literal>delete</literal>
or <literal>insert</literal>.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">object</replaceable></term>
<listitem>
<para>
Object is either <replaceable class="parameter">table</replaceable>
or <replaceable class="parameter">table</replaceable>.<replaceable
class="parameter">column</replaceable>.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">condition</replaceable></term>
<listitem>
<para>
Any SQL WHERE clause. <literal>new</literal> or
<literal>current</literal> can appear instead of an instance
variable whenever an instance variable is permissible in SQL.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">action</replaceable></term>
<listitem>
<para>
Any SQL statement. <literal>new</literal> or
<literal>current</literal> can appear instead of an instance
variable whenever an instance variable is permissible in SQL.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</REFSECT2>
</REFSYNOPSISDIV>
<REFSECT1 ID="R1-SQL-CREATERULE-1">
<REFSECT1INFO>
<DATE>1998-09-11</DATE>
</REFSECT1INFO>
<TITLE>
</refsect2>
<refsect2 id="R2-SQL-CREATERULE-2">
<refsect2info>
<date>1998-09-11</date>
</refsect2info>
<title>
Outputs
</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>
CREATE
</computeroutput></term>
<listitem>
<para>
Message returned if the rule is successfully created.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
</refsynopsisdiv>
<refsect1 id="R1-SQL-CREATERULE-1">
<refsect1info>
<date>1998-09-11</date>
</refsect1info>
<title>
Description
</TITLE>
<PARA>
</title>
<para>
The semantics of a rule is that at the time an individual instance is
accessed, updated, inserted or deleted, there is a current instance (for
retrieves, updates and deletes) and a new instance (for updates and
@@ -146,13 +137,13 @@ CREATE RULE <replaceable class="parameter">name</replaceable>
command that caused activation.
</para>
<REFSECT2 ID="R2-SQL-CREATERULE-3">
<REFSECT2INFO>
<DATE>1998-09-11</DATE>
</REFSECT2INFO>
<TITLE>
<refsect2 id="R2-SQL-CREATERULE-3">
<refsect2info>
<date>1998-09-11</date>
</refsect2info>
<title>
Notes
</TITLE>
</title>
<para>
A caution about SQL rules is in order. If the same class name
or instance variable appears in the
@@ -164,14 +155,17 @@ CREATE RULE <replaceable class="parameter">name</replaceable>
variables that are shared between these clauses. For example, the following
two rules have the same semantics:
<programlisting>
on update to EMP.salary where EMP.name = "Joe"
do update EMP ( ... ) where ...
on update to EMP-1.salary where EMP-2.name = "Joe"
do update EMP-3 ( ... ) where ...
ON UPDATE TO emp.salary WHERE emp.name = "Joe"
DO UPDATE emp ( ... ) WHERE ...
</programlisting>
<programlisting>
ON UPDATE TO emp-1.salary WHERE emp-2.name = "Joe"
DO UPDATE emp-3 ( ... ) WHERE ...
</programlisting>
Each rule can have the optional tag INSTEAD.
Without
Without
this tag, <replaceable class="parameter">action</replaceable> will be
performed in addition to the user command when the
<replaceable class="parameter">event</replaceable> in the
@@ -180,7 +174,7 @@ Without
<replaceable class="parameter">action</replaceable> part will be done
instead of the user command. In this later case, the
<replaceable class="parameter">action</replaceable> can be the keyword
NOTHING.
<literal>NOTHING</literal>.
</para>
<para>
When choosing between the rewrite and instance rule systems for a
@@ -192,25 +186,27 @@ Without
It is very important to note that the rewrite rule system
will neither detect nor process circular rules. For example, though each
of the following two rule definitions are accepted by
<productname>Postgres</productname>, the
<productname>Postgres</productname>, the
retrieve command will cause <productname>Postgres</productname> to crash:
<example>
<title>Example of a circular rewrite rule combination.</title>
<programlisting>
create rule bad_rule_combination_1 as
on select to EMP
do instead select to TOYEMP
create rule bad_rule_combination_2 as
on select to TOYEMP
do instead select to EMP
CREATE RULE bad_rule_combination_1 AS
ON SELECT TO emp
DO INSTEAD SELECT TO toyemp;
</programlisting>
<para>
<programlisting>
CREATE RULE bad_rule_combination_2 AS
ON SELECT TO toyemp
DO INSTEAD SELECT TO emp;
</programlisting>
<para>
This attempt to retrieve from EMP will cause
<productname>Postgres</productname> to crash.
<productname>Postgres</productname> to crash.
<programlisting>
select * from EMP
SELECT * FROM emp;
</programlisting></para>
</example>
@@ -219,25 +215,24 @@ select * from EMP
You must have rule definition access to a class in order
to define a rule on it. Use <command>GRANT</command>
and <command>REVOKE</command> to change permissions.
</PARA>
</REFSECT2>
</para>
</refsect2>
</refsect1>
<REFSECT1 ID="R1-SQL-CREATERULE-2">
<TITLE>
<refsect1 id="R1-SQL-CREATERULE-2">
<title>
Usage
</TITLE>
<PARA>
</title>
<para>
Make Sam get the same salary adjustment as Joe:
<programlisting>
create rule example_1 as
on update EMP.salary where current.name = "Joe"
do update EMP (salary = new.salary)
where EMP.name = "Sam"
CREATE RULE example_1 AS
ON UPDATE emp.salary WHERE current.name = "Joe"
DO UPDATE emp (salary = new.salary)
WHERE emp.name = "Sam";
</programlisting>
At the time Joe receives a salary adjustment, the event
will become true and Joe's current instance and proposed
new instance are available to the execution routines.
@@ -248,12 +243,12 @@ create rule example_1 as
<para>
Make Bill get Joe's salary when it is accessed:
<programlisting>
create rule example_2 as
on select to EMP.salary
where current.name = "Bill"
do instead
select (EMP.salary) from EMP
where EMP.name = "Joe"
CREATE RULE example_2 AS
ON SELECT TO EMP.salary
WHERE current.name = "Bill"
DO INSTEAD
SELECT (emp.salary) from emp
WHERE emp.name = "Joe";
</programlisting>
</para>
<para>
@@ -261,40 +256,40 @@ create rule example_2 as
department (<function>current_user</function> returns the name of
the current user):
<programlisting>
create rule example_3 as
on select to EMP.salary
where current.dept = "shoe" and current_user = "Joe"
do instead nothing
CREATE RULE example_3 AS
ON SELECT TO emp.salary
WHERE current.dept = "shoe" AND current_user = "Joe"
DO INSTEAD NOTHING;
</programlisting>
</para>
<para>
Create a view of the employees working in the toy department.
<programlisting>
create TOYEMP(name = char16, salary = int4)
CREATE toyemp(name = char16, salary = int4);
create rule example_4 as
on select to TOYEMP
do instead
select (EMP.name, EMP.salary) from EMP
where EMP.dept = "toy"
CREATE RULE example_4 AS
ON SELECT TO toyemp
DO INSTEAD
SELECT (emp.name, emp.salary) FROM emp
WHERE emp.dept = "toy";
</programlisting>
</para>
<para>
All new employees must make 5,000 or less
<programlisting>
create rule example_5 as
on insert to EMP where new.salary > 5000
do update newset salary = 5000
CREATE RULE example_5 AS
ON INERT TO emp WHERE new.salary > 5000
DO UPDATE NEWSET salary = 5000;
</programlisting>
</PARA>
</REFSECT1>
<REFSECT1 ID="R1-SQL-CREATERULE-3">
<TITLE>
</para>
</refsect1>
<refsect1 id="R1-SQL-CREATERULE-3">
<title>
Bugs
</TITLE>
</title>
<para>
The object in a SQL rule cannot be an array reference and
The object in a <acronym>SQL</acronym> rule cannot be an array reference and
cannot have parameters.
</para>
<para>
@@ -308,36 +303,36 @@ create rule example_5 as
text attributes. This implies that creation of rules may
fail if the rule plus its various internal representations
exceed some value that is on the order of one page (8KB).
</PARA>
</para>
</refsect1>
<REFSECT1 ID="R1-SQL-CREATERULE-4">
<TITLE>
<refsect1 id="R1-SQL-CREATERULE-4">
<title>
Compatibility
</TITLE>
<PARA>
CREATE RULE statement is a <productname>Postgres</productname>
language extension.
</PARA>
<REFSECT2 ID="R2-SQL-CREATERULE-4">
<REFSECT2INFO>
<DATE>1998-09-11</DATE>
</REFSECT2INFO>
<TITLE>
</title>
<para>
<command>CREATE RULE</command> statement is a <productname>Postgres</productname>
language extension.
</para>
<refsect2 id="R2-SQL-CREATERULE-4">
<refsect2info>
<date>1998-09-11</date>
</refsect2info>
<title>
SQL92
</TITLE>
</title>
<para>
There is no CREATE RULE statement in <acronym>SQL92</acronym>.
There is no <command>CREATE RULE</command> statement in <acronym>SQL92</acronym>.
</para>
</refsect2>
</refsect1>
</REFENTRY>
</refentry>
<!-- Keep this comment at the end of the file
Local variables:
mode: sgml
sgml-omittag:t
sgml-omittag:nil
sgml-shorttag:t
sgml-minimize-attributes:nil
sgml-always-quote-attributes:t