hi oracle lovers,
i want to know what is bind variable and how does it
improves query performence.
select ename from emp where empno= :num;
compiled
now i execute with by giving 7369 and i get the answer.
now i give 7444 ,i get the result ,but how does
oracle make it as soft parse instead of hard parse
while the two queries differ in the semantic structure.
select ename from emp where empno= 7369;
select ename from emp where empno=7444;

thr

See the example below,


-----LATE BINDING
declare
account_id VARCHAR(14) := 'CA6800003132';
begin
delete from sujit_test where account_id = account_id;
end;

---all the rows will be deleted


-----FAST BINDING
declare
account_id VARCHAR(14) := 'CA6800003132';
begin
EXECUTE IMMEDIATE 'delete from sujit_test where account_id = :1' USING account_id;
end;

---only that row(s) CA6800003132 will be deleted.


  In Late Binding the Value is assigned to the variable at the run-time whereas In Fast Binding the value is assigned at the compile time.

Sujit

Sujit Ku. Mahapatra