siddharth ranga

• Sep 29th, 2005

 

use hints /*+ <hint> */, these acts as directives to the optimizer

siddharth ranga

• Sep 29th, 2005

 

an eg for hints:

Direct use of indexes.

select /*+ index(a index_name) full(b) */ *from  table1 a, table2 bwhere  b.col1 = a.col1 and    b.col2= 'sid'and    b.col3 = 1;

Gaurav Rustogi

• Sep 7th, 2007

 

Explicitly chooses an index scan for the specified table. You can use the INDEX hint for domain, B*-tree, and bitmap indexes.

CREATE INDEX ix_customers_gender
ON customers(gender);

set autotrace traceonly explain

SELECT *
FROM customers
WHERE gender = 'M';

SELECT /*+ INDEX(customers ix_customers_gender) */ *
FROM customers
WHERE gender = 'M';