Ingres 11.2 | Forced Use of Secondary Indexes

Database Administrator Guide > Database Administrator Guide > Choosing Storage Structures and Secondary Indexes > Secondary Indexes > Forced Use of Secondary Indexes

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Forced Use of Secondary Indexes

You can force a secondary index to be used by referencing it in the query, but the optimizer must ensure that this is never necessary. For example, consider the following query:

select * from emp
where emp.name = 'Shigio';

To force it to use a secondary index, change it to the following:

select * from emp, xname
where xname.tidp = emp.tid
and xname.name = 'Shigio';

Last modified date: 08/28/2024