Postgresql 中文操作指南
37.52. table_constraints #
视图 table_constraints 包含当前用户所拥有或具有 SELECT 之外的权限的某个表的全部约束。
The view table_constraints contains all constraints belonging to tables that the current user owns or has some privilege other than SELECT on.
Table 37.50. table_constraints Columns
Table 37.50. table_constraints Columns
Column Type Description |
constraint_catalog sql_identifier Name of the database that contains the constraint (always the current database) |
constraint_schema sql_identifier Name of the schema that contains the constraint |
constraint_name sql_identifier Name of the constraint |
table_catalog sql_identifier Name of the database that contains the table (always the current database) |
table_schema sql_identifier Name of the schema that contains the table |
table_name sql_identifier Name of the table |
constraint_type character_data Type of the constraint: CHECK, FOREIGN KEY, PRIMARY KEY, or UNIQUE |
is_deferrable yes_or_no YES if the constraint is deferrable, NO if not |
initially_deferred yes_or_no YES if the constraint is deferrable and initially deferred, NO if not |
enforced yes_or_no Applies to a feature not available in PostgreSQL (currently always YES) |
nulls_distinct yes_or_no If the constraint is a unique constraint, then YES if the constraint treats nulls as distinct or NO if it treats nulls as not distinct, otherwise null for other types of constraints. |