Update sequence docs.
This commit is contained in:
parent
f20cad7870
commit
f890004cc1
@ -1,5 +1,5 @@
|
||||
<!--
|
||||
$PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.383 2005/10/03 02:21:16 momjian Exp $
|
||||
$PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.384 2005/10/03 02:46:43 momjian Exp $
|
||||
|
||||
Typical markup:
|
||||
|
||||
@ -398,28 +398,28 @@ pg_[A-Za-z0-9_] <application>
|
||||
</para>
|
||||
<para>
|
||||
In previous releases, <function>nextval()</>,
|
||||
<function>currval</>, and <function>setval()</> recorded
|
||||
sequence names as simple text strings, meaning that renaming or
|
||||
dropping a sequence used in a <command>DEFAULT</> made the
|
||||
clause invalid. This release stores all newly-created sequence
|
||||
function arguments using internal OIDs, allowing them to handle
|
||||
sequence renaming, and adding dependency information that
|
||||
prevents improper sequence removal. It also makes
|
||||
<command>DEFAULT</> clauses immune to schema search
|
||||
path changes.
|
||||
<function>currval</>, and <function>setval()</> recorded sequence
|
||||
names as simple text strings, meaning that renaming or dropping a
|
||||
sequence used in a <command>DEFAULT</> clause made the clause
|
||||
invalid. This release stores all newly-created sequence function
|
||||
arguments as internal OIDs, allowing them to handle sequence
|
||||
renaming, and adding dependency information that prevents
|
||||
improper sequence removal. It also makes <command>DEFAULT</>
|
||||
clauses immune to schema search path changes, and allows schema
|
||||
renaming.
|
||||
</para>
|
||||
<para>
|
||||
Some applications might rely on the old text-based behavior of
|
||||
run-time lookup of the sequence name. This can still be done by
|
||||
run-time lookup for sequence names. This can still be done by
|
||||
casting the argument to <type>text</>, for example
|
||||
<literal>nextval('myseq'::text)</>.
|
||||
</para>
|
||||
<para>
|
||||
Pre-8.1 schemas loaded into 8.1 will use the previous, text-based
|
||||
representation and therefore will not have these protections.
|
||||
However, it is possible to upgrade a database to the newer
|
||||
OID-based arguments. First, save this query into a file, such as
|
||||
<filename>fixseq.sql</>:
|
||||
representation and therefore will not have the features of
|
||||
OID-stored arguments. However, it is possible to upgrade a
|
||||
database loaded with pre-8.1 schemas. First, save this query into
|
||||
a file, such as <filename>fixseq.sql</>:
|
||||
<programlisting>
|
||||
SELECT 'ALTER TABLE ' ||
|
||||
pg_catalog.quote_ident(n.nspname) || '.' ||
|
||||
|
Loading…
Reference in New Issue
Block a user