...n])[WITH<backward_compatible_index_option>[,...n]][ON{filegroup_name|"default"}]::={[database_name.[owner_name].|owner_name.]table_or_view_name}<backward_compatible_index_option>::={PAD_INDEX|FILLFACTOR=fillfactor|SORT_IN_TEMPDB|IGNORE_DUP_KEY|STATISTICS_NORECOMPUTE|DROP_EXISTING}...
] table_or_view_name } <backward_compatible_index_option> ::= { PAD_INDEX | FILLFACTOR = fillfactor | SORT_IN_TEMPDB | IGNORE_DUP_KEY | STATISTICS_NORECOMPUTE | DROP_EXISTING } Azure Synapse Analytics 和并行数据仓库的语法 syntaxsql 复制 CREATE CLUSTERED COLUMNSTORE INDEX index_name ON [...
table_or_view_name 与该索引关联的表或视图的名称。 若要查看表或视图的索引详细信息,请使用 sys.indexes 目录视图。 当<database_name>.<schema_name>. 是当前数据库名称时,Azure SQL 数据库支持由三部分构成的名称 <database_name> 格式,或者 <database_name>tempdb, 以# 或##开头。 如果架构名称 dbo...
Therefore, indexes on small tables might never be used, but must still be maintained as data in the table changes. Indexes on views can provide significant performance gains when the view contains aggregations, table joins, or a combination of aggregations and joins. The view doesn't have t...
在两个区间之间计算有多少条记录的方式,在mysql中被称为index dive。如果一个SQL 用了 IN (2万个参数,或者一个子查询SQL结果集非常多的),那么mysql很有可能认为走全表扫描更快。 查看mysql的index dive参数值: SHOWVARIABLESLIKE'%dive%';-- 默认 eq_range_index_dive_limit = 200。在5.7.3版本以前,mysql...
DBA_LOBS displays the BLOBs and CLOBs contained in all tables in the database. BFILEs are stored outside the database, so they are not described by this view. This view’s columns are the same as those in ALL_LOBS. https://docs.oracle.com/en/database/oracle/oracle-database/12.2/ref...
有关创建索引的详细信息,请参阅CREATE INDEX (Transact-SQL)中的“注释”部分。 示例 本文中的 Transact-SQL 代码示例使用AdventureWorks2022或AdventureWorksDW2022示例数据库,可从Microsoft SQL Server 示例和社区项目主页下载它。 A. 创建主 XML 索引 下面的示例为CatalogDescription表的Production.ProductModel列创建主...
Creates a full-text index on a table or indexed view in a database in SQL Server and Azure SQL.
Find unused indexes in SQL Server and TSQL With SQL Sentry, you can click on the Index tab to identify unused indexes in SQL Server and TSQL. You can also view SQL Server index usage metrics to more easily discover the seeks, scans, and lookups of specific indexes (low volumes of these...
Creates a full-text index on a table or indexed view in a database in SQL Server and Azure SQL.