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Minor fixes in markup.

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Include cross-references in NOTIFY and UNLISTEN.
This commit is contained in:
Thomas G. Lockhart
1998-10-21 05:34:12 +00:00
parent 5e0ea5225f
commit 0958666ce6
5 changed files with 82 additions and 42 deletions
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35
doc/src/sgml/ref/create_sequence.sgml
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@ -234,10 +234,16 @@ CREATE SEQUENCE <replaceable class="parameter">seqname</replaceable>
to get a new number from the sequence.
The function
<function>currval('<replaceable class="parameter">seqname</replaceable>')</function>
may be used
to determine the number returned by the last call to
may be used to determine the number returned by the last call to
<function>nextval(<replaceable class="parameter">seqname</replaceable>)</function>
for the specified sequence in the current session.
The function
<function>setval('<replaceable class="parameter">seqname</replaceable>',
<replaceable class="parameter">newvalue</replaceable>)</function>
may be used to set the current value of the specified sequence.
The next call to
<function>nextval(<replaceable class="parameter">seqname</replaceable>)</function>
will return the given value plus the sequence increment.
</para>
<para>
@ -259,10 +265,8 @@ SELECT last_value FROM sequence_name;
calls to a generator.
</para>
<para>
<TITLE>
NOTE:
</TITLE>
<caution>
<para>
Unexpected results may be obtained if a cache setting greater than one
is used for a sequence object that will be used concurrently by multiple
backends. Each backend will allocate "cache" successive sequence values
@ -273,7 +277,8 @@ SELECT last_value FROM sequence_name;
will be lost. Furthermore, although multiple backends are guaranteed to
allocate distinct sequence values, the values may be generated out of
sequence when all the backends are considered. (For example, with a cache
setting of 10, backend A might reserve values 1..10 and return nextval=1, then
setting of 10, backend A might reserve values 1..10 and return nextval=1,
then
backend B might reserve values 11..20 and return nextval=11 before backend
A has generated nextval=2.) Thus, with a cache setting of one it is safe
to assume that nextval values are generated sequentially; with a cache
@ -281,7 +286,7 @@ SELECT last_value FROM sequence_name;
are all distinct, not that they are generated purely sequentially.
Also, last_value will reflect the latest value reserved by any backend,
whether or not it has yet been returned by nextval.
</para>
</caution>
<REFSECT2 ID="R2-SQL-CREATESEQUENCE-3">
<REFSECT2INFO>
@ -327,6 +332,20 @@ nextval
INSERT INTO distributors VALUES (NEXTVAL('serial'),'nothing');
</programlisting>
</para>
<para>
Set the sequence value after a COPY FROM:
<programlisting>
CREATE FUNCTION distributors_id_max() RETURNS INT4
AS 'SELECT max(id) FROM distributors'
LANGUAGE 'sql';
BEGIN;
COPY distributors FROM 'input_file';
SELECT setval('serial', distributors_id_max());
END;
</programlisting>
</para>
</REFSECT1>
<REFSECT1 ID="R1-SQL-CREATESEQUENCE-3">