diff options
Diffstat (limited to 'doc/src/sgml/catalogs.sgml')
| -rw-r--r-- | doc/src/sgml/catalogs.sgml | 63 |
1 files changed, 50 insertions, 13 deletions
diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml index 69e79c5fbd..bc5bab0a47 100644 --- a/doc/src/sgml/catalogs.sgml +++ b/doc/src/sgml/catalogs.sgml @@ -1,6 +1,6 @@ <!-- Documentation of the system catalogs, directed toward PostgreSQL developers - $Header: /cvsroot/pgsql/doc/src/sgml/catalogs.sgml,v 2.19 2001/07/15 22:48:15 tgl Exp $ + $Header: /cvsroot/pgsql/doc/src/sgml/catalogs.sgml,v 2.20 2001/08/10 18:57:32 tgl Exp $ --> <chapter id="catalogs"> @@ -532,9 +532,9 @@ <para> <structname>pg_class</structname> catalogues tables and mostly everything else that has columns or is otherwise similar to a - table. This includes indexes (but see + table. This includes indexes (but see also <structname>pg_index</structname>), sequences, views, and some - kinds of special relation kinds. Below, when we mean all of these + kinds of special relation. Below, when we mean all of these kinds of objects we speak of <quote>relations</quote>. Not all fields are meaningful for all relation types. </para> @@ -565,8 +565,8 @@ <entry><type>oid</type></entry> <entry>pg_type.oid</entry> <entry> - The data type that corresponds to this table (not functional, - only set for system tables) + The OID of the data type that corresponds to this table, if any + (zero for indexes, which have no pg_type entry) </entry> </row> @@ -631,14 +631,19 @@ <entry>reltoastidxid</entry> <entry><type>oid</type></entry> <entry>pg_class.oid</entry> - <entry>Oid of the index on the TOAST table for this table, 0 if none</entry> + <entry> + For a TOAST table, the OID of its index. 0 if not a TOAST table. + </entry> </row> <row> <entry>relhasindex</entry> <entry><type>bool</type></entry> <entry></entry> - <entry>True if this is a table and it has at least one index</entry> + <entry>True if this is a table and it has (or recently had) any indexes. + This is set by CREATE INDEX, but not cleared immediately by DROP INDEX. + VACUUM clears relhasindex if it finds the table has no indexes. + </entry> </row> <row> @@ -664,7 +669,7 @@ <entry><type>int2</type></entry> <entry></entry> <entry> - Number of columns in the relation, besides system columns. + Number of user columns in the relation (system columns not counted). There must be this many corresponding entries in <structname>pg_attribute</structname>. See also <structname>pg_attribute</structname>.<structfield>attnum</structfield>. @@ -695,14 +700,30 @@ <entry>relukeys</entry> <entry><type>int2</type></entry> <entry></entry> - <entry>unused (<emphasis>Not</emphasis> the number of unique keys or something.)</entry> + <entry>unused (<emphasis>Not</emphasis> the number of unique keys)</entry> </row> <row> <entry>relfkeys</entry> <entry><type>int2</type></entry> <entry></entry> - <entry>Number foreign keys on the table</entry> + <entry>unused (<emphasis>Not</emphasis> the number of foreign keys on the table)</entry> + </row> + + <row> + <entry>relrefs</entry> + <entry><type>int2</type></entry> + <entry></entry> + <entry>unused</entry> + </row> + + <row> + <entry>relhasoids</entry> + <entry><type>bool</type></entry> + <entry></entry> + <entry> + True if we generate an OID for each row of the relation. + </entry> </row> <row> @@ -710,8 +731,7 @@ <entry><type>bool</type></entry> <entry></entry> <entry> - unused (No, this does not say whether the table has a primary - key. It's really unused.) + True if the table has (or once had) a primary key. </entry> </row> @@ -726,7 +746,7 @@ <entry>relhassubclass</entry> <entry><type>bool</type></entry> <entry></entry> - <entry>At least one table inherits this one</entry> + <entry>At least one table inherits from this one</entry> </row> <row> @@ -875,6 +895,23 @@ </row> <row> + <entry>classoid</entry> + <entry><type>oid</type></entry> + <entry>pg_class.oid</entry> + <entry>The oid of the system catalog this object appears in</entry> + </row> + + <row> + <entry>objsubid</entry> + <entry><type>int4</type></entry> + <entry></entry> + <entry>For a comment on a table attribute, this is the attribute's + column number (the objoid and classoid refer to the table itself). + For all other object types, this field is presently zero. + </entry> + </row> + + <row> <entry>description</entry> <entry><type>text</type></entry> <entry></entry> |