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Your message has been sent to W3Schools. W3Schools is optimized for learning and training. You can rebuild a disabled nonclustered index online when the table does not have a disabled clustered index. For more information about online index operations, see Perform Index Operations Online. Creating a new clustered index enables previously disabled nonclustered indexes. For more information, see Enable Indexes and Constraints. In Object Explorer, click the plus sign to expand the database that contains the table on which you want to disable an index.
In the Disable Indexes dialog box, verify that the correct index is in the Indexes to disable grid and click OK. In Object Explorer, click the plus sign to expand the database that contains the table on which you want to disable the indexes. In the Disable Indexes dialog box, verify that the correct indexes are in the Indexes to disable grid and click OK.
To remove an index from the Indexes to disable grid, select the index and then press the Delete key. Index Name Displays the name of the index. During execution, this column also displays an icon representing the status. Table Name Displays the name of the table or view that the index was created on.
Status Displays the status of the disable operation. Possible values after execution are:. Unique indexes are used not only for performance, but also for data integrity.
A unique index does not allow any duplicate values to be inserted into the table. The basic syntax is as follows. Whether to create a single-column index or a composite index, take into consideration the column s that you may use very frequently in a query's WHERE clause as filter conditions.
Should there be only one column used, a single-column index should be the choice. Should there be two or more columns that are frequently used in the WHERE clause as filters, the composite index would be the best choice. Implicit indexes are indexes that are automatically created by the database server when an object is created. Indexes are automatically created for primary key constraints and unique constraints.
Care should be taken when dropping an index because the performance may either slow down or improve.
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