When using SQL Server 2005-based query notifications, the unique identifier isnullbecause SQL Server 2005 does not support returning unique identifiers for individual query notifications . Applies to 產品版本 .NET Framework2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4....
ALTER TABLE ADD CONSTRAINT UNIQUE(); 实例2,修改数据表 demo_department,指定部门的名称唯一,输入的 SQL 语句和运行结果如下所示。 mysql> ALTER TABLE demo_department -> ADD CONSTRAINT unique_name UNIQUE(name); Query OK, 0 rows affected (0.63 sec) Records: 0 Duplicates: 0 Warnings: 0 mysql> DES...
Using Transact-SQL To create a unique index on a table InObject Explorer, connect to an instance of Database Engine. On the Standard bar, clickNew Query. Copy and paste the following example into the query window and clickExecute.
136699Microsoft Query 中联接的使用说明 保存查询。 在“查询”菜单上,单击“运行”。 查询应按预期运行,并且不会截断“备注”字段。 状态 Microsoft 已经确认这是一个列于“适用范围”部分的 Microsoft 产品问题。 反馈 此页面是否有帮助? 是否 提供产品反馈 ...
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【实例2】把学生表student的name唯一约束删除,输入的 SQL 语句和运行结果如下所示。 mysql> alter table student drop index name; Query OK, 0 rows affected Records: 0 Duplicates: 0 Warnings: 0 mysql> desc student; +---+---+---+---+---+---+ | Field | Type | Null | Key | Default ...
Try the below query DECLARE @Random NVARCHAR(10);--To store 4 digit random number DECLARE @Final NVARCHAR(MAX)--Final unique random number DECLARE @Upper INT; DECLARE @Lower INT This will create a random number between 1 and 9999
You can set the UniqueRecords property in the query's property sheet or in SQL view of the Query window. Note: You set this property when you create a new query by using an SQL statement. The DISTINCTROW predicate corresponds to the UniqueRecords property setting. The DISTINCT predicate corre...
getSQLStatement getValidTimeStateDateRange getValidTimeStateDateTimeRange getValidTimeStateQueryType groupByField groupByFieldCount handle hasRangeOrFilter havingFilter havingFilterCount importSession inReport insert_recordset interactive isCompositeQuery IsManagedValid isPureUnionAll isUnionType kernelhandle level...
In Object Explorer, connect to an instance of Database Engine. On the Standard bar, select New Query. Copy and paste the following example into the query window and select Execute. The example creates a table and defines a unique constraint on the column TransactionID. SQL Copy USE ...