Hi,

I am trying out various functions in SQL.

I did not understand the second form of INSTR.it looks like this
INSTR(COL_name,string,num1,num2).Can anyone explain?

And in TRIM function even though I specified lead it trims both the ends
Ex:-select ename,trim('a' in ename)lead from emp;

In round function,e=what actually happens if we gave the second argument negative?

ex:-select round(45.3,-2) from dual;why does this return 0??