Correct my Decode Function

Question

Hi,
I created a table and inserted some records into the table.
I am trying to find the output using decode function using the below query.
select marks,decode(marks,(marks>70),'A',(marks>60 and marks<70),'B',(marks>50 and marks<60),'C') from stud_mrks
But I am getting error as
ERROR at line 1:
ORA-00907: missing right parenthesis
Can anyone please correct me.
Thanks

Answer 1

If you have to use DECODE -- for example teacher has asked to in that way in Homework ;) then this example may help you.
SQL> SELECT ename,sal,DECODE(sign(sal-1000),-1,'LOW',
  2                          DECODE(sign(sal-2000),-1,'MEDIUM','HIGH')) FROM emp;
ENAME                                      SAL DECODE
SMITH                                      800 LOW
ALLEN                                     1600 MEDIUM
WARD                                      1250 MEDIUM
JONES                                     2975 HIGH
MARTIN                                    1250 MEDIUM
BLAKE                                     2850 HIGH
CLARK                                     2450 HIGH
SCOTT                                     3000 HIGH
KING                                      5000 HIGH
TURNER                                    1500 MEDIUM
ADAMS                                     1100 MEDIUM
ENAME                                      SAL DECODE
JAMES                                      950 LOW
FORD                                      3000 HIGH
MILLER                                    1300 MEDIUM
999999                                     100 LOW
ABCDEFGHIJKLMNOPQRSTUVWXYZAAAAAA           100 LOW
MY#@ ' "ABC                                100 LOW
17 rows selected.
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