SQL joining 2 tables with some overlapping values - mysql

Question

I am trying to create one table out of the following 2 tables and running into a lot of problems.
Table 1 has the following:
Month,
Salesperson_Assigned,
Product1_Revenue
Table 2 has the following (different product):
Month,
Salesperson_Assigned,
Product2_Revenue
The problem is that while all the months are the same, there are some salespeople in Table 1 not in Table 2, and vice versa. Obviously the revenue is different. I want to join the tables to look like Month, Salesperson, Product1_revenue + Product2_revenue.
Here's the query I'm using:
SELECT
Table1.month,
Table1.salesperson_assigned,
sum(Table1.revenue + Table2.revenue)
FROM
Table1
INNER JOIN Table 2 ON (Table1.month = Table2.month) AND (Table1.salesperson_assigned = Table2.salesperson_assigned)
The output isn't correct even though I confirmed the revenue values in each individual table are correct. The output seems to be making up additional values for the salespeople who appear in only 1 table for the field that should be null.
Anyone had any advice for how to join the 2 tables properly so it acts similar to a pivot table, adding the unique values to the "salesperson assigned" column and adding the revenue for both columns, but when a salesperson is in only ONE table having it respect that there is a zero value for revenue?

Answer 1

did you tried this way:
SELECT
Table1.month,
Table1.salesperson_assigned,
sum(Table1.revenue + Table2.revenue)
FROM
Table1 FULL OUTER JOIN Table2 on (Table1.month = Table2.month AND Table1.salesperson_assigned = Table2.salesperson_assigned)

Answer 2

Ideally for these type of situations FULL OUTER JOINS are useful - but apparently MySQL does not support FULL OUTER JOINS see: Full Outer Join in MySQL
Update (without using right outer join):
create table table1
(month int
,salesperson_assigned int
,Product1_revenue int);
create table table2
(month int
,salesperson_assigned int
,Product2_revenue int);
insert into table1 values(1,10,100);
insert into table1 values(2,10,200);
insert into table1 values(1,11,40);
insert into table1 values(2,11,800);
insert into table1 values(3,11,400);
insert into table2 values(1,10,100);
insert into table2 values(2,10,200);
insert into table2 values(1,12,40);
insert into table2 values(2,12,200);
select
table1.month
,table1.salesperson_assigned
,ifnull(table1.Product1_revenue,0) as Product1_revenue
,ifnull(table2.Product2_revenue,0) as Product2_revenue
,ifnull(table1.Product1_revenue,0)+ifnull(table2.Product2_revenue,0) as total_revenue
from table1
left outer join table2
on table1.salesperson_assigned=table2.salesperson_assigned and table1.month=table2.month
union
select
table2.month
,table2.salesperson_assigned
,ifnull(table1.Product1_revenue,0) as Product1_revenue
,ifnull(table2.Product2_revenue,0) as Product2_revenue
,ifnull(table1.Product1_revenue,0)+ifnull(table2.Product2_revenue,0) as total_revenue
from table2
left outer join table1
on table2.salesperson_assigned=table1.salesperson_assigned and table1.month=table2.month
order by 2,1;
returns:
Month salesperson_assigned Product1_revenue Product2_revenue total_revenue
1 10 100 100 200
2 10 200 200 400
1 11 40 0 40
2 11 800 0 800
3 11 400 0 400
1 12 0 40 40
2 12 0 200 200
ps:Please consider posting code to reproduce your data so that you can get quicker response.