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Last round of reference page editing.

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This commit is contained in:
Peter Eisentraut
2003-05-04 02:23:16 +00:00
parent ac5fdea687
commit d1b4327d02
31 changed files with 3335 additions and 4547 deletions
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52
doc/src/sgml/ref/set_transaction.sgml
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@@ -1,9 +1,5 @@
<!-- $Header: /cvsroot/pgsql/doc/src/sgml/ref/set_transaction.sgml,v 1.13 2003/03/25 16:15:44 petere Exp $ -->
<!-- $Header: /cvsroot/pgsql/doc/src/sgml/ref/set_transaction.sgml,v 1.14 2003/05/04 02:23:16 petere Exp $ -->
<refentry id="SQL-SET-TRANSACTION">
<docinfo>
<date>2000-11-24</date>
</docinfo>
<refmeta>
<refentrytitle id="SQL-SET-TRANSACTION-TITLE">SET TRANSACTION</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
@@ -15,12 +11,12 @@
</refnamediv>
<refsynopsisdiv>
<synopsis>
<synopsis>
SET TRANSACTION
[ ISOLATION LEVEL { READ COMMITTED | SERIALIZABLE } ] [ READ WRITE | READ ONLY ]
SET SESSION CHARACTERISTICS AS TRANSACTION
[ ISOLATION LEVEL { READ COMMITTED | SERIALIZABLE } ] [ READ WRITE | READ ONLY ]
</synopsis>
</synopsis>
</refsynopsisdiv>
<refsect1>
@@ -28,8 +24,8 @@ SET SESSION CHARACTERISTICS AS TRANSACTION
<para>
The <command>SET TRANSACTION</command> command sets the transaction
characteristics of the current SQL-transaction. It has no effect on
any subsequent transactions. <command>SET SESSION
characteristics of the current transaction. It has no effect on any
subsequent transactions. <command>SET SESSION
CHARACTERISTICS</command> sets the default transaction
characteristics for each transaction of a session. <command>SET
TRANSACTION</command> can override it for an individual
@@ -80,7 +76,9 @@ SET SESSION CHARACTERISTICS AS TRANSACTION
or data-modification statement (<command>SELECT</command>,
<command>INSERT</command>, <command>DELETE</command>,
<command>UPDATE</command>, <command>FETCH</command>,
<command>COPY</command>) of a transaction has been executed.
<command>COPY</command>) of a transaction has been executed. See
<xref linkend="mvcc"> for more information about transaction
isolation and concurrency control.
</para>
<para>
@@ -117,25 +115,23 @@ SET default_transaction_isolation = '<replaceable>value</replaceable>'
<refsect1 id="R1-SQL-SET-TRANSACTION-3">
<title>Compatibility</title>
<refsect2 id="R2-SQL-SET-TRANSACTION-4">
<title>SQL92, SQL99</title>
<para>
Both commands are defined in the SQL standard.
<literal>SERIALIZABLE</literal> is the default transaction
isolation level in <acronym>SQL</acronym>; in PostgreSQL it is
<literal>READ COMMITED</literal>, but you can change it as
described above. <productname>PostgreSQL</productname> does not
provide the isolation levels <literal>READ UNCOMMITTED</literal>
and <literal>REPEATABLE READ</literal>. Because of multiversion
concurrency control, the <literal>SERIALIZABLE</literal> level is
not truly serializable. See <xref linkend="mvcc"> for details.
</para>
<para>
<option>SERIALIZABLE</option> is the default transaction isolation level in
<acronym>SQL</acronym>. <productname>PostgreSQL</productname> does
not provide the isolation levels <option>READ UNCOMMITTED</option>
and <option>REPEATABLE READ</option>. Because of multiversion
concurrency control, the <option>SERIALIZABLE</option> level is not
truly serializable. See <xref linkend="mvcc"> for details.
</para>
<para>
In <acronym>SQL</acronym> there is one other transaction
characteristic that can be set with these commands: the size of
the diagnostics area. This concept is not supported in
<productname>PostgreSQL</productname>.
</para>
</refsect2>
<para>
In the SQL standard, there is one other transaction characteristic
that can be set with these commands: the size of the diagnostics
area. This concept is only for use in embedded SQL.
</para>
</refsect1>
</refentry>