To view the table name, join sys.indexes with sys.tables on object_id. Using the ONLINE = ON and MOVE TO options requires additional temporary disk space.Īfter an index is dropped, the resulting heap appears in the sys.indexes catalog view with NULL in the name column. You cannot drop a clustered index online if the index is disabled on a view, or contains text, ntext, image, varchar(max), nvarchar(max), varbinary(max), or xml columns in the leaf-level data rows.
For a complete description of the ONLINE option, see CREATE INDEX (Transact-SQL). Only one clustered index can be dropped online at a time. When you specify ONLINE = ON, queries and modifications to the underlying data and associated nonclustered indexes are not blocked by the DROP INDEX transaction. Use MOVE TO to drop the clustered index and move the resulting table to another filegroup or partition scheme in a single transaction. You can set the following index options when you drop a clustered index: MAXDOP, ONLINE, and MOVE TO. ALTER INDEX REBUILD has optimizations to prevent the overhead of rebuilding the nonclustered indexes. To do this, using ALTER INDEXis more efficient, especially for clustered indexes. Sometimes indexes are dropped and re-created to reorganize or rebuild the index, such as to apply a new fill factor value or to reorganize data after a bulk load. When indexes with 128 extents or more are dropped, the Database Engine defers the actual page deallocations, and their associated locks, until after the transaction commits. An XML index or spatial index cannot be dropped by using the backward compatible syntax. index_name is maintained for backward compatibility. Manually created statistics are not dropped. When the clustered index of an indexed view is dropped, all nonclustered indexes and auto-created statistics on the same view are automatically dropped.
DROPKEY STUDIO OFFLINE
Review SQL Server Index Architecture and Design Guide for details.Īn index cannot be dropped if the filegroup in which it is located is offline or set to read-only. This does not apply to columnstore indexes or in-memory data stores. In rowstore indexes, SQL Server implements a B+ tree. SQL Server documentation uses the term B-tree generally in reference to indexes. Specifies the default location for the FILESTREAM data. If no location is specified and the table is not partitioned, the data is included in the default FILESTREAM filegroup. Specifies a FILESTREAM filegroup for FILESTREAM data. If you specify a partition scheme for MOVE TO, you must use the same partition scheme for FILESTREAM ON. If no location is specified and the table is partitioned, the table is included in the same partition scheme as the existing clustered index. The partition scheme must have already been created by executing either CREATE PARTITION SCHEME or ALTER PARTITION SCHEME. Specifies a partition scheme for the FILESTREAM data. If a partition scheme is not specified, the data will be located in the same partition scheme as was defined for the clustered index. FILESTREAM ON is not valid for indexed views or nonclustered indexes. You can specify either a partition scheme or filegroup as the new location, but the partition scheme or filegroup must already exist. The data is moved to the new location in the form of a heap. Specifies a location to move the FILESTREAM table that currently is in the leaf level of the clustered index. table_or_view_name.index_nameĪpplies to: SQL Server 2008 (10.0.x) and later. Transact-SQL syntax conventions Syntax - Syntax for SQL Server (All options except filegroup and filestream apply to Azure SQL Database.)
XML indexes cannot be dropped using backward compatible syntax. Avoid using this syntax in new development work, and plan to modify applications that currently use the feature. The syntax defined in will be removed in a future version of Microsoft SQL Server.
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