The CHECK constraint is used to limit the value range that can be placed in a column.If you define a CHECK constraint on a column it will allow only certain values for this column.If you define a CHECK constraint on a table it can limit the values in certain columns based on values ...
可以使用 SQL Server Management Studio 或 Transact-SQL 在表中创建检查约束,以指定 SQL Server 的一个或多个列中可接受的数据值。 要详细了解如何添加列约束,请参阅 ALTER TABLE column_constraint。有关详细信息,请参阅 Unique 约束和 check 约束。
SqlBuiltinScalarFunctionCallExpression SqlCaseExpression SqlCastExpression SqlChangeTrackingContext SqlCheckConstraint SqlCheckConstraint Properties Methods Explicit Interface Implementations ISqlTableElement.AsColumnDefinition ISqlTableElement.AsConstr...
CONSTRAINT_NAMEsysname條件約束名稱。 CHECK_CLAUSEnvarchar(4000)Transact-SQL 定義語句的實際文字。 系統檢視 (Transact-SQL) 資訊架構檢視 (Transact-SQL) sys.check_constraints (Transact-SQL) sys.objects (Transact-SQL) 其他資源 事件 FabCon Vegas
Getting an error with following sql query with mysql v8 which was working with v5.7. Create table test ( empId char(36) not null, tolerance decimal(5,2) not null check (pct > 0 and pct <= 100), primary key (empId) ); ERROR 3813 (HY000): Column check constraint 'test_chk_1' re...
CREATE TABLE CheckTbl (col1 int, col2 int); GO CREATE FUNCTION CheckFnctn() RETURNS int AS BEGIN DECLARE @retval int SELECT @retval = COUNT(*) FROM CheckTbl RETURN @retval END; GO ALTER TABLE CheckTbl ADD CONSTRAINT chkRowCount CHECK (dbo.CheckFnctn() >= 1 ); GO 添加的 CHECK 约...
A CHECK constraint returns TRUE when the condition it is checking is not FALSE for any row in the table. A CHECK constraint works at the row level. If a table that has just been created does not have any rows, any CHECK constraint on this table is considered valid. This situation can ...
CREATE TABLE CheckTbl (col1 int, col2 int); GO CREATE FUNCTION CheckFnctn() RETURNS int AS BEGIN DECLARE @retval int SELECT @retval = COUNT(*) FROM CheckTbl RETURN @retval END; GO ALTER TABLE CheckTbl ADD CONSTRAINT chkRowCount CHECK (dbo.CheckFnctn() >= 1 ); GO ...
CheckConstraint 型別會公開下列成員。 方法 展開資料表 名稱說明 Accept 指定之訪客的進入點。 (覆寫 TSqlFragment.Accept(TSqlFragmentVisitor)。) AcceptChildren 在具有指定之訪客的子系上呼叫 Accept。 (覆寫 Constraint.AcceptChildren(TSqlFragmentVisitor)。) Equals 判斷指定的 Object 和目前的 Object ...
A CHECK constraint returns TRUE when the condition it is checking is not FALSE for any row in the table. A CHECK constraint works at the row level. If a table that has just been created does not have any rows, any CHECK constraint on this table is considered valid. This situation can ...