Sql Server关于create index include带有包含列的索引 By including nonkey columns, you can create nonclustered indexes that cover more queries. This is because the nonkey columns have the following benefits: They can be data types not allowed as index key columns. They are not considered by the ...
Using SQL Server Management Studio to create an index with nonkey columns In Object Explorer, select the plus sign to expand the database that contains the table on which you want to create an index with nonkey columns. Select the plus sign to expand theTablesfolder. ...
Using SQL Server Management StudioTo create an index with nonkey columnsIn Object Explorer, click the plus sign to expand the database that contains the table on which you want to create an index with nonkey columns. Click the plus sign to expand the Tables folder. Click the plus sign...
在INCLUDE 列表中列名不能重复,且不能同时用于键列和非键列。 如果对表定义了聚集索引,则非聚集索引始终包含聚集索引列。 有关详细信息,请参阅 Create Indexes with Included Columns。允许除 text、 ntext和image之外的所有数据类型。 从 SQL Server 2012 (11.x) 和 Azure SQL 数据库开始,如果任何一个指定的...
CreateIndexStatement.IncludeColumns 属性 项目 2013/04/26 本文内容 语法 请参阅 Gets the list of the include columns.命名空间: Microsoft.SqlServer.TransactSql.ScriptDom 程序集: Microsoft.SqlServer.TransactSql.ScriptDom(在 Microsoft.SqlServer.TransactSql.ScriptDom.dll 中)...
1.SQL 创建索引 使用CREATE 语句创建索引 CREATE INDEX index_name ON table_name(column_name,column_name) include(score) 普通索引 CREATE UNIQUE INDEX index_name ON table_
SQL Server 性能调优3 之索引(Index)的维护 前言 前一篇的文章介绍了通过建立索引来提高数据库的查询性能,这其实只是个开始。后续如果缺少适当的维护,你先前建立的索引甚至会成为拖累,成为数据库性能的下降的帮凶。 查找碎片 消除碎片可能是索引维护最常规的任务,微软官方给出的建议是当碎片等级为 5% - 30% 之间时...
The CREATE INDEX statement creates a partitioning index or a secondary index and an index space at the current server. The columns included in the key of the index are columns of a table at the current server. Invocation for CREATE INDEX This statement can be embedded in an application ...
The SQL Server 2005 Database Engine does not allow creating a unique index on columns that already include duplicate values, whether or not IGNORE_DUP_KEY is set to ON. If this is tried, the Database Engine displays an error message. Duplicate values must be removed before a unique index ...
视图的聚集索引必须唯一。 无论IGNORE_DUP_KEY 是否设置为 ON,SQL Server 2005 数据库引擎都不允许为已包含重复值的列创建唯一索引。否则,数据库引擎会显示错误消息。必须先删除重复值,然后才能为一列或多列创建唯一索引。唯一索引中使用的列应设置为 NOT NULL,因为在创建唯一索引时,会将多个空值视为重复值。