INSTR() function is taking more time

Question

im using the below query select query in my procedure.
select distinct SUPPLIER_CIRCUIT_ID from SUPPLIER_DATA
where INSTR(i.SYSTEM_CIRCUIT_ID,SUPPLIER_CIRCUIT_ID) > 0;
I am taking SYSTEM_CIRCUIT_ID in cursor.
This query is taking more time. Is that possiblt to create function based index and speed up the query?

Answer 1

Hi,
Welcome to the forum!
993620 wrote:
im using the below query select query in my procedure.
select distinct SUPPLIER_CIRCUIT_ID from SUPPLIER_DATA
where INSTR(i.SYSTEM_CIRCUIT_ID,SUPPLIER_CIRCUIT_ID) > 0;
I am taking SYSTEM_CIRCUIT_ID in cursor.Show exactly what you're doing.
Whenever you have a problem, post a complete test script that people can run to re-create the problem and test their ideas.
See te forum FAQ {message:id=9360002}
This query is taking more time. Is that possiblt to create function based index and speed up the query?Sorry, unless you doing something very specific (such as alwyas looking for the same sub-string) then a function-based index won't help.
Oracle sells a separate product, called Oracle Text, for this kind of searching.
You might try LIKE:
WHERE  i.SYSTEM_CIRCUIT_ID LIKE  '%' || SUPPLIER_CIRCUIT_ID || '%'If you're using a cursor, then that's probably slowing the process down much more than the part you're showing.