Article for:SQL Server▾ Query below lists table (and view) indexes. Query selectschema_name(t.schema_id) +'.'+ t.[name]astable_view,casewhent.[type] ='U'then'Table'whent.[type] ='V'then'View'endas[object_type], i.index_id,casewheni.is_primary_key =1then'Primary key'wheni...
Coveres the basics of indexes in SQL Server. Clustered versus non-clustered, composite, and unique indexes, as well as tips for chosing the columns and SQL to create, delete, and rename indexes. Relational databases use indexes to find data quickly when a query is processed. Creating and re...
如果在表名下打开Indexes节点,您将看到新的索引名ix_parts_id,类型为Clustered(聚集)。 此时再执行以下语句时,SQL Server直接遍历索引(聚集索引查找)以定位具体行,这比扫描整个表快得多。 SELECT part_id, part_name FROM production.parts WHERE part_id=5;...
适用于:SQL ServerAzure SQL 数据库Azure SQL 托管实例Azure Synapse AnalyticsAnalytics Platform System (PDW)Microsoft Fabric SQL 数据库 使用标准 SQL 大容量加载和渗透插入方法将数据加载到列存储索引的选项和建议。 将数据加载到列存储索引是任何数据仓库过程必不可少的组成部分,因为它会将数据...
/* DBCC IND ( ['database name'|database id],-- the database to use table name,-- the table name to list results index id,-- an index_id from sys.indexes; -1 shows all indexes and IAMs, -2 just show IAMs )*/--IndexId = 1 and PrevPageFID = 0(第一页)DBCCIND('数据库名'...
SQL Server中所有的索引都是平衡二叉树结构,平衡树的意思是所有叶子节点到根节点的距离都相同,SQL Server进行索引查找时总是从索引的根节点开始,并从根跳到下一级的相应页,并继续从一个级别跳到下一个级别,直到达把可以查找键的叶子页。所有叶级节点到底跟的距离都是相同的,这意味着一次查找操作在叶读取上的成本...
-- List unused indexes SELECT OBJECT_NAME(i.[object_id]) AS [Table Name] , i. name FROM sys.indexes AS i INNER JOIN sys.objects AS o ON i.[object_id] = o.[object_id] WHERE i.index_id NOT IN ( SELECT s.index_id FROM sys.dm_db_index_usage_stats AS s WHERE s.[object_id...
value(N'(./text())[1]',N'varchar(8000)'),1,2,''),'') AS Index_List FROM sys.tables AS t LEFT OUTER JOIN sys.indexes i ON t.object_id=i.object_id AND is_hypothetical = 0 AND i.index_id > 0 GROUP BY t.Object_ID; 我在老的测试数据库上执行这个测试,对象名称比较短。 代码...
argumentlist $idx, "HireDate", $true $idx.IndexedColumns.Add($icol2) #Set the index properties. $idx.IndexKeyType = [Microsoft.SqlServer.Management.SMO.IndexKeyType]::DriUniqueKey $idx.IsClustered = $false $idx.FillFactor = 50 #Create the index on the instance of SQL Serve...
语法(SQLServer2000) DBCC SHOWCONTIG [ ( { table_name | table_id| view_name | view_id } [ , index_name | index_id ] ) ] [ WITH { ALL_INDEXES | FAST [ , ALL_INDEXES ] | TABLERESULTS [ , { ALL_INDEXES } ] [ , { FAST | ALL_LEVELS } ] ...