Doing calculations on a table or group of tables

Question

Table A
Name          Length
REDBOX          45
GREENBOX     67
YELLOWBOX     89
PINKBOX          23
How would I write a query that would count the number of rows in the table
which is this case is 4 (count* maybe) , add up the four values in length
(using sum () I think) and then multiply both values together.
So ( num of rows ) * ( sum (length)) = Result.
I would like to displat the Result as an extra row but not sure you can do that...

Answer 1

hi
SQL> ed
Wrote file afiedt.buf
1 select t.table_name,count(column_name)
2 from user_tables t, user_tab_columns c
3 where t.table_name = c.table_name
4* group by t.table_name
SQL> /
SQL> /
TABLE_NAME COUNT(COLUMN_NAME)
BIN$48zoh9RLRoq/Fj6gXkvdxg==$0 8
BIN$C0999MpPRjGrEnn4tSnBeg==$0 5
BONUS 4
DEPT 3
DEPTT 3
DUMMY_T2 2
EMP 8
EMP1 8
EMP2 8
EMPHIST 8
EMPLOYEES_TEMP 3
TABLE_NAME COUNT(COLUMN_NAME)
EMPPROJ 4
EROW 1
LOGIN 2
PARENT 3
PR 3
SAL 2
SALGRADE 3
T1 1
TEST 3
TSTAMP 1
USERDATA 4
TABLE_NAME COUNT(COLUMN_NAME)
USERDATAUSER 4
VALID_RANGE 13
24 rows selected.
mohammadi
Message was edited by:
Mohdidubai52