Gbase 8C system table PG_ database

pg_database System tables store information about available databases .

name	type	quote	describe
oid	oid		Row identifier （ Hidden attribute , Must be explicitly selected to display ）
datname	name		Database name
datdba	oid	pg_authid.oid	The owner of the database , Usually the user who created it
encoding	int4		The character encoded number of this database （pg_encoding_to_char() This number can be converted into a coded name ）
datcollate	name		Of this database LC_COLLATE
datctype	name		Of this database LC_CTYPE
datistemplate	bool		If it is true , Then this database can be used by anyone with CREATEDB Privileged user cloning ; If it is false , only The super user or the owner of the database can clone it .
datallowconn	bool		If false, no one can connect to this database . This can be used to protect template0 The database is not modified .
datconnlimit	int4		Set the maximum number of concurrent connections that can connect to this database .-1 There is no limit .
datlastsysoid	oid		The last system in the database OID, Yes pg_dump Particularly useful
datfrozenxid	xid		All transactions before ID It has been replaced with a permanent （“ Frozen ”) Business ID. This is used to track whether the database needs to be cleaned up , In order to organize affairs ID Loopback or allow pg_xact Contracted . It is the of all tables in this database pg_class.relfrozenxid The minimum value of .
datminmxid	xid		All previous multi transactions ID It has been replaced with a transaction in the database ID. This is used to track whether the database needs to be clear , In order to organize affairs ID Loopback or allow pg_multixact Contracted . It is in this database All the tables pg_class.relminmxid The minimum value of .
dattablespace	oid	pg_tablespace.oid	The default tablespace for this database . In this database , all pg_class.reltablespace by 0 All tables will be stored in this table space , In particular, non shared system directories will be included .
datacl	aclitem[]		Access right