ACCESS SQL : How to calculate wage (multiply function) and count no.of working days (count, distinct) of each staff between 2 dates - sql

Question

I need to create a form to summarize wage of each employees according to Date_start and Date_end that I selected.
I have 3 related tables.
tbl_labor
lb_id | lb_name | lb_OT ($/day) | If_social_sec
1 | John | 10 | yes
2 | Mary | 10 | no
tbl_production
pdtn_date | lb_id | pdtn_qty(pcs) | pd_making_id
5/9/12 | 1 | 200 | 12
5/9/12 | 1 | 40 | 13
5/9/12 | 2 | 300 | 12
7/9/12 | 1 | 48 | 13
13/9/12 | 2 | 220 | 14
15/9/12 | 1 | 20 | 12
20/9/12 | 1 | 33 | 14
21/9/12 | 2 | 55 | 14
21/9/12 | 1 | 20 | 12
tbl_pdWk_process
pd_making_id | pd_cost($/dozen) | pd_id
12 | 2 | 001
13 | 5 | 001
14 | 6 | 002
The outcome will look like this:
lb_name | no.working days | Total($)| OT payment | Social_sec($)| Net Wage |
John | 4 | 98.83 | 20 (2x10) | 15 | 103.83 (98.83+20-15)|
Mary | 2 | 160 | 10 (1x10) | 0 | 170 (160+10-0) |
My conditions are:
Wage are calculate between 2 dates that i specify eg. 5/9/12 - 20/9/12
Wage must be calculated from (pd_cost * pdtn_qty). However, pdtn_qty was kept in 'pieces' whereas pd_cost was kept in 'dozen'. Therefore the formula should be (pdtn_qty * pd_cost)/12
Add OT * no. of OT days that each worker did (eg. John had 2 OT days, Mary 1 OT day)
Total wages must be deducted eg. 15$ if If_social_sec are "TRUE"
Count no. of working days that each employees had worked.
I've tried but i couldn't merge all this condition together in one SQL statement, so could you please help me. Thank you.

Answer 1

OK this is really messy. Mainly because Access has no COUNT(DISTINCT ) option. So counting the working days is a mess. If you can skip that, then you can drop all the pdn1,pdn2,pdn3 stuff. But id does work. Couple of notes
1. I think your maths is not quite right in the example given, I make it like this:
2 I've used the IIF clause to simulate 2 OT for john, 1 for mary. You'll need to change that. Good luck.
select
lab.lb_name,
max(days),
sum(prod.pdtn_qty * pdWk.pd_cost / 12) as Total ,
max(lab.lb_OT * iif(lab.lb_id=1,2,1)) as OTPayment,
max(iif(lab.if_social_sec='yes' , 15,0 ) ) as Social_Sec,
sum(prod.pdtn_qty * pdWk.pd_cost / 12.00) +
max(lab.lb_OT * iif(lab.lb_id=1,2,1)) -
max(iif(lab.if_social_sec='yes' , 15,0 ) ) as NetWage
from
tbl_labor as lab,
tbl_production as prod,
tbl_pdWk_process as pdwk,
(select pdn2.lb_id, count(pdn2.lb_id) as days from
(select lb_id
from tbl_production pdn1
where pdn1.pdtn_date >= #9/5/2012#
and pdn1.pdtn_date <= #2012-09-20#
group by lb_id, pdtn_date ) as pdn2
group by pdn2.lb_id) as pdn3
where prod.pdtn_date >= #9/5/2012#
and prod.pdtn_date <= #2012-09-20#
and prod.lb_id = lab.lb_id
and prod.pd_making_id = pdwk.pd_making_id
and lab.lb_id = pdn3.lb_id
group by lab.lb_name
OK to add the items not in production table, you'll need to append something like this:
Union
select lab.lb_name,
0,
0,
max(lab.lb_OT * iif(lab.lb_id=1,2,1)) ,
max(iif(lab.if_social_sec='yes' , 15,0 ) ),0
from tbl_labor lab
where lb_id not in ( select lb_id from tbl_production where pdtn_date >= #2012-09-05# and pdtn_date <= #2012-09-20# )
group by lab.lb_name
Hope this helps.