CHECK Constraint in Existing Table We can add theCHECKconstraint to an existing table by using theALTER TABLEclause. For example, let's add theCHECKconstraint to theamountcolumn of an existingOrderstable. -- add CHECK constraint without nameALTERTABLEOrdersADDCHECK(amount >0); Here's how we c...
MySQL / SQL Server / Oracle / MS Access: ALTERTABLEPersons ADDCHECK(Age>=18); To allow naming of aCHECKconstraint, and for defining aCHECKconstraint on multiple columns, use the following SQL syntax: MySQL / SQL Server / Oracle / MS Access: ...
确保SQL模式设置为支持汉字字符集。 # 自动化脚本mysql-uroot-p-e"SET GLOBAL sql_mode = 'STRICT_TRANS_TABLES';"mysql-uroot-p-e"ALTER TABLE test_table ADD CONSTRAINT CHECK (检查字段 > 0);" 1. 2. 3. <8.0>=8.0确认MySQL版本我的版本是?升级到8.x版本设置SQL模式更改表结构 验证测试 在实施了...
SQL Server Azure SQL 数据库 Azure SQL 托管实例 检查当前数据库中指定表上的指定约束或所有约束的完整性。 Transact-SQL 语法约定 语法 syntaxsql DBCCCHECKCONSTRAINTS[ (table_name|table_id|constraint_name|constraint_id) ] [WITH[ {ALL_CONSTRAINTS|ALL_ERRORMSGS} ] [ , ] [NO...
constraintPK_UserId_MyUserInfo primarykeyclustered,--主键 --1创建外键 dIdintnotnull constraintFK_MyUserInfo_tbDept foreignkey referencestbDept(dId), UserCIPchar(18)notnull constraintUQ_UserCIP_MyUserInfounique,--唯一约束 UserJSIDchar(6)notnull ...
'ID唯一标识',name VARCHAR(10) NOT NULL UNIQUE COMMENT '姓名',age INT COMMENT '年龄',status CHAR(1) DEFAULT '1' COMMENT '状态',gender CHAR(1) COMMENT '性别',CONSTRAINT check_age CHECK (age > 0 AND age <= 120),CONSTRAINT check_status CHECK (status IN ('1', '2'))) COMMENT '...
ALTER TABLE 表名 ADD CONSTRAINT 约束名 KEY(本表内要加以外键约束的字段) REFERENCES 其他表(要被其他表用以外键约束的字段); 然后当我们想删除时: ALTER TABLE 表名 DROP FOREIGN KEY外键约束名; 但是像我之前建立sc表的时候,我并没有给外键约束创建名字,那应该怎么删除呢?
Überprüft die Integrität einer angegebenen Einschränkung oder aller Einschränkungen einer angegebenen Tabelle in der aktuellen Datenbank. Transact-SQL-Syntaxkonventionen Syntax DBCC CHECKCONSTRAINTS [ ( table_name | table_id | constraint_name | constraint_id ) ] [ WITH [ { ALL_CONST...
Syntax error in CHECK CONSTRAINT clause. (Error 3765)Article 06/14/2014 Expand table This error occurs when using SQL DLL to define a CHECK constraint. It occurs when the search condition (SELECT statement) in the CHECK clause references an invalid table or column name....
in a loss of precision, an error occurs. Note Constraint expression evaluation the SQL mode in effect at evaluation time. If any component of the expressiondepends on the SQL mode, different results may occur for different uses of the table unless the SQL mode is the same during all...