CODEWITHSUNDEEP
mysqlrelational-databasecalculated-field
user1770468
user1770468

Reputation: 1

mysql: calculate between tables

Here is my problem:

I have two tables, lets name it "main" and "Ex"

table main looks like: (pseudo code)

nr | points|
A1 | 5     |
A2 | 3     |
A3 | 4     |
B1 | 2 |
B2 | 4 |

Table ex looks like:

Pnr | Ex1 | Ex2 | Pmax |
P1  | A1  | B1  |  7 [calculated from table main]
P2  | A2  | B1  |  5 [calculated from table main]

How to I get a realation between these two tables, to calculate Pmax?

thx a lot.

c.

Upvotes: 0

Views: 105

Answers (1)

Taryn
Taryn

Reputation: 247870

It seems like this is what you want:

select e.pnr,
  e.ex1,
  e.ex2,
  sum(points) Pmax
from main m
inner join ex e
  on m.nr = e.ex1
  or m.nr = e.ex2
group by e.pnr, e.ex1, e.ex2

See SQL Fiddle with Demo

Upvotes: 2

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