UPDATE_RULE varchar(11) Transact-SQL 語句違反這個條件約束所定義的引用完整性時所採取的動作。 傳回下列其中一項:NO ACTIONCASCADESET NULLSET DEFAULT 如果此條件約束的 ON UPDATE 上指定 NO ACTION,則不會將條件約束中所參考的主鍵更新傳播到外鍵。 如果主鍵的這類更新會導致引用完整性違規,因為至少有一個外鍵...
"Comparable data types for referential constraints", conforming SQL language shall not contain a <referencing columns> in which the data type of each referencing column is not the same as the data type of the corresponding referenced column. NOTE — The Conformance Rules of Subclause 9.12, "G...
REFERENTIAL_CONSTRAINTS (Transact-SQL)项目 2025/01/03 12 个参与者 反馈 适用于: SQL Server Azure 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...
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...
postgresql 信息模式中referential_constraints.unique_constraint_* 列的值为空假设约束名为test_def_abc_...
The value of the constraintON DELETEattribute. The possible values areCASCADE,SET NULL,SET DEFAULT,RESTRICT,NO ACTION. TABLE_NAME The name of the table. This value is the same as in theTABLE_CONSTRAINTStable. REFERENCED_TABLE_NAME The name of the table referenced by the constraint. ...
postgresql 信息模式中referential_constraints.unique_constraint_* 列的值为空假设约束名为test_def_abc_...
MySQL Error [1109]: "Unknown table 'referential_constraints' in information_schema" Type HELP for debugger help, or (SB-EXT:EXIT) to exit from SBCL. restarts (invokable by number or by possibly-abbreviated name): 0: [ABORT] Exit application ...
before all other constraints, including those referential constraints with modifying rules such as CASCADE or SET NULL. An update rule of NO ACTION is enforced after other referential constraints. Note that the SQLSTATE returned is different depending on whether the update rule is RESTRICT or NO ...
Reinert: Access Path Support for Referential Integrity in SQL2 - Härder, Joachim - 1996 () Citation Context ...ar database constraints. Most DBMSs already support foreign (super)keys; adding support for CRs does not seem very difficult. The techniques for maintaining referential integrity ...