... UNIQUE(column_name) ); 定义多列的unique约束 UNIQUE(column_name1,column_name2),定义约束并重命名CONSTRAINT new_name UNIQUE(column_name) 2)ALTER TABLE 时的 SQL UNIQUE 约束 ALTER TABLE table_name ADD UNIQUE (column_name) 添加多列的unique约束 UNIQUE(column_name1,column_name2),定义约束并...
SQL 复制 EXEC sp_describe_first_result_set N'SELECT b2 AS b3 FROM v', NULL, 2; 结果集如下。展开表 is_hiddencolumn_ordinalnamesource_schemasource_tablesource_columnis_part_of_unique_key 0 1 B3 dbo v B2 0 1 2 ROWSTAT NULL NULL NULL 0...
比如说生活中的小数据:全国新冠疫情疫苗接种人数就用int,银行必须使用decimal类型、因为客户数据重要,需要用到大内存的数据类型,全国人口的出生数据记录,为了日后能继续使用因此需要设置为datetime或者datetime2即可,两者之时精度不同罢了。。。 3.SQL语言 数据准备 创建Student 表结构 CREATE DATABASE Stu USE Stu --...
SQL_DESC_AUTO_UNIQUE_VALUE SQLINTEGER ARD:未使用的 APD:未使用的 IRD:R IPD:未使用 ARD:未使用的 APD:未使用的 IRD:D IPD:未使用 SQL_DESC_BASE_COLUMN_NAME SQLCHAR * ARD:未使用的 APD:未使用的 IRD:R IPD:未使用 ARD:未使用的 APD:未使用的 IRD:D IPD:未使用 SQL_DESC_BASE_TABLE_NAME SQ...
The names of server-level firewall settings must be unique. If the name of the setting provided for the stored procedure already exists in the firewall settings table, the starting and ending IP addresses are updated. Otherwise, a new server-level firewall setting is created....
Other SQL Server logins that might enable TDE or other SQL Server encryption features. There's one-to-one mapping between credentials and logins. That is, each login must have a unique credential. Modify this Transact-SQL script in the following ways: Edit the IDENTITY argument (DocsSampleEKM...
[US] } ) SELECT NON EMPTY HIERARCHIZE (AddCalculatedMembers ({DrillDownLevel ({[Product].[All Products]}) }) ) DIMENSION PROPERTIES PARENT_UNIQUE_NAME ON COLUMNS FROM [Adventure Works] WHERE ([Geography].[State-Province].x, [Date].[Calendar].[Calendar Quarter].&[2003]&[4] ,[Measures]...
If each underlying table doesn't have a unique index and an ISOSCROLLcursor or if a Transact-SQLKEYSETcursor is requested, the cursor is automatically aSTATICcursor. Ifselect_statementcontains anORDER BYclause in which the columns aren't unique row identifiers, aDYNAMICcursor is converted to aKE...
This name should be unique among all the database-level directory names in the SQL Server instance. Uniqueness comparison is case-insensitive, regardless of collation settings. This option must be set before creating a FileTable in this database. <HADR_options> ::= Applies to: SQL Server See...
SQL Másolás SELECT i.name AS index_name , i.type_desc , i.is_unique , ds.type_desc AS filegroup_or_partition_scheme , ds.name AS filegroup_or_partition_scheme_name , i.ignore_dup_key , i.is_primary_key , i.is_unique_constraint , i.fill_factor , i.is_padded , i.is_...