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[Siddheart22]

hi,

I need to decide which all columns should be used to create indexes on a table.
I realise that it depends on the WHERE predicates, but I need to know hw much it helps in case of and IN or LIKE clause.

Please post any info related to this

Cheers

[kolusu]

Siddheart22,

The rule of thumb for table design is, if you are going to search on a column, create an index on that column . "search on a column" is actually one of several criteria for creating an index.

consider creating an index if the column is used in

- the WHERE clause (i.e. to search on)
- the WHERE clause or ON conditions (to join tables)
- the GROUP BY or ORDER BY clauses

one caveat for creating indexes is whether in fact they would actually be used.

suppose there *is* an index on surname, but you wanted to go LIKE '%d
_________________
Kolusu
www.linkedin.com/in/kolusu

[Siddheart22]

Thanks Kolusu