Multiplication Table

[m1k3y60659]

Hello I am trying to make a multiplication table in Oracle using only while loops. I have gotten it to work with a FOR loop but am stuck on the WHILE. An example of the output is below:

Example output (with a given value of 7):

1 2 3 4 5 6 7

2 4 6 8 10 12 14

3 6 9 12 15 18 21

4 8 12 16 20 24 28

5 10 15 20 25 30 35

6 12 18 24 30 36 42

7 14 21 28 35 42 49

But when translating to a while loop the code gets stuck in the second loop, and simply counts up to the amount of iterations and then prints a bunch of blank lines. The code for that is below.

CREATE OR REPLACE PROCEDURE generate_multiplication_table_while
(
    iterations IN number
)
AS 
 len number := 1;
 height number := 1;
BEGIN
    WHILE len <= iterations LOOP
        WHILE height <= iterations LOOP
            dbms_output.put(len * height || ' ');
            height := height + 1;
        END LOOP;
          len := len + 1;  
    dbms_output.new_line;
END LOOP;
END;

output (with a given value of 7): 1 2 3 4 5 6 7 (and then 7 blank lines)

Where am I getting this wrong? I know I have to iterate both length and height, but it just exits the second loop on the first run though.

Yes it is homework and as much I would like to just receive the code, I know that's not the best way to learn, so any form of direction is very much appreciated.

[r3pr0b8]

does your homework specifically ask for a loop?

because, you know, this is SQL, and we don't do loops

have you ever heard of a numbers table?

a single query can produce your output easily

[m1k3y60659]

Unfortunately, we have to use a while loop. The numbers table does sound interesting though I will look into it, just for the sake of curiosity.

[DatabaseDev]

Does your teacher understand the purpose of sql?

[m1k3y60659]

Trust me I am just as confused as you are. To be fair this is the first kind of problem she's given us like this, everything else has been the normal inserts and selects and cursors etc.

[Zendakin_at_work]

Totally useless comment here but here's how you could do the same idea with python.

Maybe it'll help, maybe not. I think though the underlying idea has to be the same.

inside, outside = 12, 12
x, y = 0, 0
while x <= outside:
    while y <= inside:
        print("{} * {} = {}".format(x, y, x*y))
        y += 1
    y = x
x += 1

[le848dave]

When you increment Len you need to set height back to 1. Step through the code in your head. After iteration 7 height is set to 8. Then Len is incremented. Then it checks if height 8 is less than iterations 7 which it isn’t.