SQL 型 V4.3.5 参考指南 系统视图 MySQL 租户系统视图 字典视图 information_schema.REFERENTIAL_CONSTRAINTS 更新时间:2025-05-16 15:41:14 编辑 说明 该视图从 V2.2.77 版本开始引入。 功能描述 用于展示外键约束的元数据。 字段说明 字段名称类型是否可以为 NULL描述 CONSTRAINT_CATA
REFERENTIAL_CONSTRAINTS (Transact-SQL) 项目 2025/01/03 12 个参与者 反馈 适用于:SQL ServerAzure SQL 数据库Azure SQL 托管实例 为当前数据库中的每个 FOREIGN KEY 约束返回一行。 该信息架构视图返回当前用户对其拥有权限的对象的相关信息。 若要从这些视图中检索信息,请指定 INFORMATION_SCHEMA.view_name 的完...
postgresql 信息模式中referential_constraints.unique_constraint_* 列的值为空假设约束名为test_def_abc_...
REFERENTIAL_CONSTRAINTS (Transact-SQL)03/01/2023 Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Returns one row for each FOREIGN KEY constraint in the current database. This information schema view returns information about the objects to which the current user h...
postgresql 信息模式中referential_constraints.unique_constraint_* 列的值为空假设约束名为test_def_abc_...
If the name of a referential constraint is specified, it must be different from all other names of referential constraints for the referencing table. If no referential constraint name is specified, the database system assigns a unique name (based on the referencing table). Referencing Columns (re...
SQL: 1999 defines its column constraints to be syntactic shorthand for table constraints. SQL: 1999 also provides the user with a different kind of constraint that is not attached to a particular table. This constraint, called an assertion, is a standalone constraint in a schema and is ...
information_schema.REFERENTIAL_CONSTRAINTS 更新时间:2024-01-16 09:32:10 分享 功能 用于展示外键约束的元数据。 说明 从V2.2.77 版本开始引入。 字段说明 字段名称类型是否可以为 NULL描述 CONSTRAINT_CATALOG varchar(64) NO 该值始终为 def CONSTRAINT_SCHEMA varchar(128) NO 约束所属库的名称 CONSTRAINT_NAME...
However, the order in which Db2 enforces constraints can affect the result of the operation. Therefore, you should be aware of the restrictions on the definition of delete rules and on the use of certain statements. The restrictions relate to the following SQL statements: CREATE TABLE, ALTER ...
TheREFERENTIAL_CONSTRAINTStable has these columns: CONSTRAINT_CATALOG The name of the catalog to which the constraint belongs. This value is alwaysdef. CONSTRAINT_SCHEMA The name of the schema (database) to which the constraint belongs. CONSTRAINT_NAME ...