Indexes usage:
1> Too many indexes / Too few indexes - both are equally bad for the system
- Too few :: Full table scan. SELECT Queries will take time.
- Too many :: DML operation may get slow, as they have to update page indexing.
2> Never put index on column which is regularly updated.
3> All SELECT queries should be indexed properly. Exception can be taken:
- Column with low cardinality. (like M/F or Y/N)
- Column which is updated often.
4> Log queries which are not using indexes.
5> Check explain plan for the queries been captured.
1> Too many indexes / Too few indexes - both are equally bad for the system
- Too few :: Full table scan. SELECT Queries will take time.
- Too many :: DML operation may get slow, as they have to update page indexing.
2> Never put index on column which is regularly updated.
3> All SELECT queries should be indexed properly. Exception can be taken:
- Column with low cardinality. (like M/F or Y/N)
- Column which is updated often.
4> Log queries which are not using indexes.
5> Check explain plan for the queries been captured.
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