Starting with SQL Server 2012 (11.x) and Azure SQL Database, if any one of the specified non-key columns are varchar(max), nvarchar(max), or varbinary(max) data types, the index can be built or rebuilt using the ONLINE option.
Create an indexed view: a T-SQL example The following example creates a view and an index on that view, in the AdventureWorks database. SQL Copy --Set the options to support indexed views. SET NUMERIC_ROUNDABORT OFF; SET ANSI_PADDING, ANSI_WARNINGS, CONCAT_NULL_YIELDS_NULL, ARITHABORT, ...
In SQL Server CREATE INDEX command creates a relational index on a table or view. Also called a rowstore index because it is either a clustered or nonclustered btree index. You can create a rowstore index before there is data in the table. Use a rowstore index to improve query performance,...
Create an indexed view: a T-SQL example The following example creates a view and an index on that view, in the AdventureWorks database. SQL Copy --Set the options to support indexed views. SET NUMERIC_ROUNDABORT OFF; SET ANSI_PADDING, ANSI_WARNINGS, CONCAT_NULL_YIELDS_NULL, ARITHABORT, ...
To create a unique index on a table, using: SQL Server Management Studio Transact-SQLBefore You BeginBenefits of a Unique IndexMulticolumn unique indexes guarantee that each combination of values in the index key is unique. For example, if a unique index is created on a combination of LastNa...
To removeINDEXfrom a table, we can use theDROP INDEXcommand. For example, SQL Server DROPINDEXColleges.college_index; PostgreSQL, Oracle DROPINDEXcollege_index; MySQL ALTERTABLECollegesDROPINDEXcollege_index; Here, the SQL command removes an index namedcollege_indexfrom theCollegestable. ...
CREATE INDEX 语句用于对数据库表定义索引。 可以对 XML 数据或关系数据定义索引。 CREATE INDEX 语句还用于创建索引规范(就是用来向优化器指示数据源表具有索引的元数据)。 调用 此语句可以嵌入在应用程序中,也可通过动态 SQL 语句来发出。 它是一个可执行语句,仅当 DYNAMICRULES 运行行为对于程序包有效时才能动态...
When a column only has a few relevant values for queries, you can create a filtered index on the subset of values. The resulting index will be smaller and cost less to maintain than a full-table nonclustered index defined on the same key columns. For example, consider a filtered index in...
When a column only has a few relevant values for queries, you can create a filtered index on the subset of values. The resulting index will be smaller and cost less to maintain than a full-table nonclustered index defined on the same key columns. For example, consider a filtered index in...
Using Transact-SQL to create an index with nonkey columns 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. SQL Copy USE AdventureWorks2022; GO -- Creates a...