1 ALTERTABLEdbo.YourTableADDIDINTIDENTITY 2 ALTERTABLEdbo.YourTableADDCONSTRAINTPK_YourTablePRIMARYKEY(ID) Or by one line ALTERTABLEdbo.YourTableADDIDINTIDENTITYCONSTRAINTPK_YourTablePRIMARYKEYCLUSTERED See-- https://stackoverflow.com/questions/4862385/sql-server-add-auto-increment-primary-key-to-exist...
2.添加字段:ALTER TABLE 表名 ADD 字段名 数据类型[属性]; 3.修改字段:ALTER TABLE 表名 CHANGE 原字段名 新字段名 数据类型[属性]; 4.删除字段:ALTER TABLE 表名 DROP 字段名; 2.添加主键 1.语法:ALTER TABLE 表名 ADD CONSTRAINT 主键名 PRIMARY KEY 表名(主键字段); 3.添加外键 1.语法:ALTER TABL...
.DateTime) tab1.Columns.Add(col3) ' Create the ftable tab1.Create() ' Define Index object on the table by supplying the Table1 as the parent table and the primary key name in the constructor. Dim pk As New Index(tab1, "Table1_PK") pk.IndexKeyType = IndexKeyType.DriPrimaryKey '...
General error: 3750 Unable to create or change a table without a primary key, when the system variable 'sql_require_primary_key' is set. Add a primary key to the table or unset this variable to avoid this message. Note that tables without a primary key can cause performance problems in ...
PRIMARY KEY (`ID`) ) ENGINE=InnoDB AUTO_INCREMENT=6356897 DEFAULT CHARSET=utf8; 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 现在在TB002上的C1列增加一个外键指向TB001的主键,有如下三种创建方式: 方式1:直接创建外键 查询:ALTER TABLE TB002 ADD CONSTRAINT `FK_C1` FOREIGN KEY (`...
创建一个名为 myRangePS1 的分区方案,该方案使用 ALL TO 语法将 myRangePF1 分区函数中的所有分区分配给 PRIMARY 文件组。 在myRangePS1 分区方案中创建一个名为 PartitionTable 的表,并指定名为 col1 的列为分区依据列。在“对象资源管理器” 中,...
] referenced_table_name [ ( ref_column ) ] | CHECK ( logical_expression ) } <table_constraint> ::= [ CONSTRAINT constraint_name ] { { PRIMARY KEY | UNIQUE } { NONCLUSTERED ( column_name [ ASC | DESC ] [ ,... n ]) | NONCLUSTERED HASH ( column_name [ ,... n ] ) WITH ...
题目使用下列SQL语句创建教师表: CREATE TABLE 教师表(教师编号 I PRIMARY KEY,; 姓名 C(8) NOT NULL,; 职称 C(10) DEFAULT "讲师") 如果要删除“职称”字段的DEFAULT约束,正确的SQL语句是___。相关知识点: 试题来源: 解析 A 反馈 收藏
] referenced_table_name [ ( ref_column ) ] | CHECK ( logical_expression ) } <table_constraint> ::= [ CONSTRAINT constraint_name ] { { PRIMARY KEY | UNIQUE } { NONCLUSTERED ( column_name [ ASC | DESC ] [ ,... n ]) | NONCLUSTERED HASH ( column_name [ ,... n ] ) WITH ...
[ PARTITION ] source_partition_number_expression ] TO target_table [ PARTITION target_partition_number_expression ] [ WITH ( <low_priority_lock_wait> ) ] } [ ; ] -- ALTER TABLE options < table_constraint > ::= [ CONSTRAINT constraint_name ] { {PRIMARY KEY | UNIQUE } { NONCLUSTERED ...