Execute immediate with using clause to pass column name dynamically

Question

Hai,
Is there any way using execute immeidate to pass the column name dynamically. I used to pass the column value as dynamic with the help of "Using clause" . But if i use to pass column name, it is giving numberic error at run time. Eg,. for testing has been given below.
1. Column value as dynamic, which is working correctly.
create or replace function testexeimm (acctnum char)
return number as
acctbal number;
begin
execute immediate 'select balance from acct_master where acct_no=:a' into acctbal using acctnum;
return acctbal;
end;
2. Column name as dynamic which is not working
create or replace function testexeimm (colnam char)
return char as
acctbal char;
begin
execute immediate 'select :a from ch_acct_mast where rownum=1' into acctbal using colnam;
return acctbal;
end;
Any help in this regard will be highly appericated.
Regards
Sridhar

Answer 1

So the variable has to be numeric too:
create or replace function testexeimm (colnam char)
return number as
acctbal number;
begin
execute immediate 'select '|||colnam||' from ch_acct_mast where rownum=1' into acctbal;
return acctbal;
end;Max
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