Can any one tell me how to increase the performance of a
sql query ie what are the performance tips in creating or
writing a sql query !!?
Answer Posted / hutashan
use Inline view to eleminate large number of rows
Avoid implicit datatype conversion
Avoid using function on an indexed column
Avoid comparing column value with NULL
Outer Join
Use OR carefully
Do not use outer join unless absolutely necessary. Degree
of optimizing outer join permutation is VERY LIMITED
Instead: Consider using default values in the base table to
avoid outer join
Do not outer join to a view. This typically results in a
non-mergable view execution plan
Always use NOT EXISTS instead of NOT IN
Remove DISTINCT keyword from SELECT if UNION is used
| Is This Answer Correct ? | 0 Yes | 0 No |
Post New Answer View All Answers
What is compound trigger?
Explain ddl statements in pl/sql?
What is index example?
Explain normalization and what are the advantages of it?
Does inner join return duplicate rows?
Define commit, rollback and savepoint?
what are the different type of sql's statements ? : Sql dba
how to write date and time literals? : Sql dba
How can a function retun more than one value in oracle with proper example?
How long does it take to learn pl sql?
How do I clear the screen in sql plus?
What is the purpose of a secondary key?
Are pl sql variables case sensitive?
Can we commit in trigger?
Can a foreign key be null?