How do you optimize SQL queries ?
- 6 Answers
- 33286 Views
- CarrizalSoft Technologies, Infosys, Oracle, I also Faced
- E-Mail Answers
Answer Posted / hutashan
Avoid implicit datatype conversion
Avoid using function on an indexed column
Avoid comparing column value with NULL
Outer Join
Use OR carefully
Always use NOT EXISTS instead of NOT IN
Use UNION ALL whenever possible (no implicit sorts)
UNION will sort the result set for each SELECT before
combining the final result set
Remove DISTINCT keyword from SELECT if UNION is used
| Is This Answer Correct ? | 6 Yes | 0 No |
Post New Answer View All Answers
What are character functions in sql?
What is the difference between delete and truncate statement in sql?
how many columns can be used for creating index? : Sql dba
Do foreign keys improve performance?
Why do we need cursor in pl sql?
What are different joins used in sql?
What is time based sql injection?
What is a clob in sql?
How to move files from one directory to another in pl sql?
How do I run a sql query?
What is where clause in sql?
Which table is left in join?
Which language is used in sql?
What is a dirty read sql?
What does pragma mean?
