Primary key, referential integrity, and check constraints.

主键、引用完整性和检查约束。

youdao

Constraints are rules that help preserve the integrity of data in a table.

约束是有助于保持表中数据的完整性的规则。

youdao

Constraints are rules that help preserve the integrity of data in a table.

约束是有助于保持表中数据的完整性的规则。

youdao