| column_name AS computed_column_expression } [ ,...n ] | [ WITH CHECK | WITH NOCHECK ] ADD { < table_constraint > } [ ,...n ] | DROP { [ CONSTRAINT ] constraint_name | COLUMN column } [ ,...n ] | { CHECK | NOC
Add Column 列名 数据类型 列级约束 Drop Column 列名 Cascade/Restrict Alter Column 列名 数据类型 Modify Column 列名 数据类型(modify用于修改列属性) *约束: Add 表级约束 Add Constraint 约束名 约束条件 Drop Constraint 约束名 Cascade/Restrict【默认】 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 1...
ALTER TABLE 表名 ADD CONSTRAINT @name DEFAULT (0) FOR [字段名]对字段约束进行更改 --删除约束 ALTER TABLE tablename Drop CONSTRAINT 约束名 --修改表中已经存在的列的属性(不包括约束,但可以为主键或递增或唯一) ALTER TABLE tablename alter column 列名 int not null --添加列的约束 ALTER TABLE tab...
SQL Server Azure SQL Database Azure SQL Managed Instance SQL database in Microsoft Fabric Specifies the properties of a PRIMARY KEY, FOREIGN KEY, UNIQUE, or CHECK constraint that is part of a new column definition added to a table by usingALTER TABLE. ...
Microsoft Fabric 中 SQL Server、Azure SQL 数据库、Azure SQL 托管实例、SQL 数据库的语法 syntaxsql [CONSTRAINTconstraint_name] { [NULL|NOTNULL] {PRIMARYKEY|UNIQUE} [CLUSTERED|NONCLUSTERED] [WITHFILLFACTOR= fillfactor ] [WITH(index_option[, ...n ] ) ] [ON{partition_scheme_name(partition_colum...
] type_name REBUILD [ [ NONCLUSTERED ] WITH ( BUCKET_COUNT = bucket_count ) ] } | ADD { <column_definition> | <computed_column_definition> | | | <column_index> } [ ,...n ] | DROP [ { CONSTRAINT [ IF EXISTS ] { constraint_name } [ ,...n ] | INDEX [ IF EXISTS ] ...
4. Adding Column and Constraint while altering TABLE 1 ALTER TABLETable_Name 2 ADD CountryId INT; 3 ALTER TABLETable_Name 4 ADD CONSTRAINT FK_CountryId FOREIGN KEY (CountryId) REFERENCES dbo.DimCountry(CountryId); --- --- 5. Occurred error "SQL Server Cannot drop database <dbname> becau...
To enforce a tree by using constraints, a computed column that defines the parent of each node can be created with a foreign key constraint back to the primary key ID. SQL კოპირება CREATE TABLE Org_T3 ( EmployeeId HIERARCHYID PRIMARY KEY, ParentId AS EmployeeId....
适用于: SQL Server 2016(13.x)及更高版本 Azure SQL 数据库azure SQL 托管实例Microsoft Fabric 中的SQL 数据库 系统版本控制时态表中的数据使用常规数据操作语言 (DML) 语句进行修改,但有一个重要的区别:无法直接修改时间段列数据。 数据更新时,它就是版本控制的,每个已更新...
Use SQL Server Management Studio Add a new computed column InObject Explorer, expand the table for which you want to add the new computed column. Right-clickColumnsand selectNew Column. Enter the column name and accept the default data type (nchar(10)). The Database Engine determines the...