Oracle simple Select query optimization -


i have below simple dynamic select query 

select relationship    dime_master   cin=? , ssn=? , account_number=?

the table has 1,083,701 records. query takes 11 12 secs execute expensive. dime_master table has account, card_number indexes. please me optimize query query execution time under fraction of second.

look @ predicate information:

--------------------------------------  1 - filter(to_number("dime_master"."ssn")=226550956              , to_number("dime_master"."account_number")=4425050005218650              , to_number("dime_master"."cin")=00335093464)

the type of columns nvarchar, parameters in query numbers.
oracle must cast numbers strings, not smart in casting.
oracles , fortune-tellers not right ;)

these casts prevents query using indices.

rewrite query using explicit conversion into:

select relationship    dime_master   cin=to_char(?) , ssn=to_char(?) , account_number=to_char(?)

then run command:

exec dbms_stats.gather_table_stats( user, 'dime_master' );

and run query , show new explain plan.

please not paste explain plans here, unreadable,
please use pastebin instead, , paste links here, thank you.

look @ simple example, shows why need explicit casts:

create table "dime_master" (    "account_number" nvarchar2(16) ); insert dime_master select round( dbms_random.value( 1, 100000 )) dual connect level <= 100000; commit; create index dime_master_acc_ix on dime_master( account_number );  explain plan select * dime_master account_number = 123;  select * table( dbms_xplan.display );  plan hash value: 1551952897  --------------------------------------------------------------------------------- | id  | operation         | name        | rows  | bytes | cost (%cpu)| time     | --------------------------------------------------------------------------------- |   0 | select statement  |             |     3 |    54 |    70   (3)| 00:00:01 | |*  1 |  table access full| dime_master |     3 |    54 |    70   (3)| 00:00:01 | ---------------------------------------------------------------------------------  predicate information (identified operation id): ---------------------------------------------------     1 - filter(to_number("account_number")=123)     explain plan select * dime_master account_number = to_char( 123 );  select * table( dbms_xplan.display ); plan hash value: 3367829596  --------------------------------------------------------------------------------------- | id  | operation        | name               | rows  | bytes | cost (%cpu)| time     | --------------------------------------------------------------------------------------- |   0 | select statement |                    |     3 |    54 |     1   (0)| 00:00:01 | |*  1 |  index range scan| dime_master_acc_ix |     3 |    54 |     1   (0)| 00:00:01 | ---------------------------------------------------------------------------------------  predicate information (identified operation id): ---------------------------------------------------     1 - access("account_number"=u'123')

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