diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/ddl.sgml | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/doc/src/sgml/ddl.sgml b/doc/src/sgml/ddl.sgml index 3c53973b762..abe3b582016 100644 --- a/doc/src/sgml/ddl.sgml +++ b/doc/src/sgml/ddl.sgml @@ -1,4 +1,4 @@ -<!-- $PostgreSQL: pgsql/doc/src/sgml/ddl.sgml,v 1.42 2005/07/14 06:17:35 neilc Exp $ --> +<!-- $PostgreSQL: pgsql/doc/src/sgml/ddl.sgml,v 1.43 2005/08/12 01:35:53 tgl Exp $ --> <chapter id="ddl"> <title>Data Definition</title> @@ -871,7 +871,7 @@ CREATE TABLE order_items ( The object identifier (object ID) of a row. This column is only present if the table was created using <literal>WITH OIDS</literal>, or if the <xref linkend="guc-default-with-oids"> - configuration variable was enabled. This column is of type + configuration variable was set. This column is of type <type>oid</type> (same name as the column); see <xref linkend="datatype-oid"> for more information about the type. </para> @@ -992,7 +992,13 @@ CREATE TABLE order_items ( <listitem> <para> A unique constraint should be created on the OID column of each - table for which the OID will be used to identify rows. + table for which the OID will be used to identify rows. When such + a unique constraint (or unique index) exists, the system takes + care not to generate an OID matching an already-existing row. + (Of course, this is only possible if the table contains fewer + than 2<superscript>32</> (4 billion) rows, and in practice the + table size had better be much less than that, or performance + may suffer.) </para> </listitem> <listitem> @@ -1005,9 +1011,8 @@ CREATE TABLE order_items ( <listitem> <para> The tables in question should be created using <literal>WITH - OIDS</literal> to ensure forward compatibility with future - releases of <productname>PostgreSQL</productname>. It is - planned that <literal>WITHOUT OIDS</> will become the default. + OIDS</literal>. As of <productname>PostgreSQL</productname> 8.1, + <literal>WITHOUT OIDS</> is the default. </para> </listitem> </itemizedlist> |