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6 lip 2011 · How to use index in select statement? this way: SELECT * FROM table1 USE INDEX (col1_index,col2_index) WHERE col1=1 AND col2=2 AND col3=3; SELECT * FROM table1 IGNORE INDEX (col3_index) WHERE col1=1 AND col2=2 AND col3=3; SELECT * FROM t1 USE INDEX (i1) IGNORE INDEX (i2) USE INDEX (i2); And many more ways check this
14 cze 2020 · Here is how you can force an index to be used with a query with the help of an index hint. In the above query, we are forcing the index FK_Sales_Invoices_AccountsPersonID to the index. We can always pass the name of the index in the WITH clause and that index will be used for the query.
19 lis 2024 · N. Use the INDEX optimizer hint. The following example shows two ways to use the INDEX optimizer hint. The first example shows how to force the optimizer to use a nonclustered index to retrieve rows from a table. The second example forces a table scan by using an index of 0.
19 kwi 2018 · SQL Server indexes can be also created indirectly by defining the PRIMARY KEY and the UNIQUE constraint within the CREATE TABLE or ALTER TABLE statements. SQL Server will create a unique clustered index to enforce the PRIMARY KEY constraint unless you already define a clustered index on that table.
Select ALL columns. If you want to return all columns, without specifying every column name, you can use the SELECT * syntax:
This tutorial shows you how to use SQL Server indexes with included columns to improve the query performance by using practical examples.
The SQL Server uses indexes of a table provided that the select or update or delete statement contained the “WHERE” clause and moreover the where condition column must be an indexed column. If the select statement contains an “ ORDER BY ” clause then also the indexes can be used.
