alter table Info add constraint pk primary key(Test4) --constraint 取约束名,不然数据库会随机取名,因为在SQLserver数据库只能通过约束名删除主键约束。 --删除主键约束:在SQLserver不能使用【alter table 表名 drop primary key】来删除主键,只能用标准的删除约束名删除。不过在MySQL可以使用。
);2.查看约束的定义信息--查看表的约束SQL>SELECTowner,constraint_name,constraint_type,table_name,status,deferrable,validatedFROMuser_constraintsORDERBYtable_name; OWNER CONSTRAINT_NAME C TABLE_NAME STATUS DEFERRABLE VALIDATED--- --- - --- --- --- ---ROBINSON SYS_C005543 C TB_CONSTRAINT_1 ENA...
--查找Check约束 select * from sys.check_constraints chk select * from sys.tables tab SELECT tab.name AS [表名], chk.name AS [Check约束名], chk.definition FROM sys.check_constraints chk JOIN sys.tables tab ON (chk.parent_object_id = tab.object_id) ---查找唯一约束 select * from sys...
Cannot drop a SQL Database cannot drop database because currently its in use cannot drop table cannot find tables in SSMS? Cannot get data of the row from OLE DB provider "OraOLEDB.Oracle" for linked server Cannot grant, deny, or revoke permissions to sa, dbo, entity owner, information_...
chk.definitionFROMsys.check_constraints chkJOINsys.tables tabON(chk.parent_object_id=tab.object_id) ---查找唯一约束select*fromsys.indexes idxwhereidx.is_unique_constraint=1 SELECTtab.nameAS[表名], idx.nameAS[约束名称], col.nameAS[约束列名]FROMsys.indexes idxJOINsys.index_columns idxColON(id...
建立新的叢集索引可啟用先前停用的非叢集索引。 如需詳細資訊,請參閱Enable Indexes and Constraints。 如果資料表為堆積,則所有非叢集索引會重建。 權限 若要執行ALTER INDEX,至少需要資料表或檢視表的ALTER權限。 使用SQL Server Management Studio 停用索引 ...
创建一个新的聚集索引将启用以前禁用的非聚集索引。 有关详细信息,请参阅Enable Indexes and Constraints。 如果表是一个堆,将重新生成所有非聚集索引。 权限 若要执行ALTER INDEX,至少需要对表或视图具有ALTER权限。 使用SQL Server Management Studio 禁用索引 ...
SQL Drop Table Examples with T-SQL and SQL Server Management Studio Disable, enable, drop and recreate SQL Server Foreign Keys Best practices for SQL Server database ALTER table operations Script all Primary Keys, Unique Constraints and Foreign Keys in a SQL Server database using T-SQL ...
In SQL Server, you cannot drop a table if it is referenced by a FOREIGN KEY constraint. You have to either drop the child tables before removing the parent table, or remove foreign key constraints. This article provides a Transact-SQL script to drop fo
Drop objects in target but not in source This option is a “hammer” that drops all objects in the target database that are not also in the source. This option overrides any data-loss options. Drop constraints, indexes, dml triggers Treats constraints, indexes and dml ...