SQL update with hard-coded column names - sql

Question

I need help creating a SQL update for the following example (with sample data):
Table 1: DETAILTRAN
Structure: VENDOR CHAR(10), EMPLOYEE CHAR(10), WEEK INT
VENDOR EMPLOYEE WEEK
VEN01 EMP01 1
VEN01 EMP01 1
VEN02 EMP03 1
VEN03 EMP02 1
VEN01 EMP01 2
VEN01 EMP01 2
VEN01 EMP03 2
VEN03 EMP02 2
VEN02 EMP01 3
VEN02 EMP01 3
VEN02 EMP03 3
VEN03 EMP03 3
Table 2: SUMMARTRAN (that needs to be updated)
Structure: WEEK01 INT, WEEK02 INT, WEEK03 INT, VENDOR CHAR(10), EMPLOYEE CHAR(10)
The results of SQL Update this table (SUMMARTRAN) should look like this:
WEEK01 WEEK02 WEEK03 VENDOR EMPLOYEE
2 3 0 VEN01
1 0 3 VEN02
1 1 1 VEN03
2 2 2 EMP01
1 1 0 EMP02
1 1 2 EMP03

Answer 1

You can approach this using grouping sets and conditional aggregation:
select vendor, employee,
sum(case when week = 1 then 1 else 0 end) as week01,
sum(case when week = 2 then 1 else 0 end) as week02,
sum(case when week = 3 then 1 else 0 end) as week03
from DETAILTRAN
group by grouping sets ((vendor), (employee));
You can incorporate this into an insert, statement for summartran:
insert into summertran(vendor, employee, week01, week02, week03)
select vendor, employee,
sum(case when week = 1 then 1 else 0 end) as week01,
sum(case when week = 2 then 1 else 0 end) as week02,
sum(case when week = 3 then 1 else 0 end) as week03
from DETAILTRAN
group by grouping sets ((vendor), (employee));

Answer 2

Try this
with VENDOR as
(
select isnull(count(case when WEEK = 1 then WEEK end),0) WEEK01,
isnull(count(case when WEEK = 2 then WEEK end),0) WEEK02 ,
isnull(count(case when WEEK = 3 then WEEK end),0) WEEK03 ,
VENDOR
from DETAILTRAN
group by VENDOR
),EMPLOYEE as
(
select isnull(count(case when WEEK = 1 then WEEK end),0) WEEK01,
isnull(count(case when WEEK = 2 then WEEK end),0) WEEK02 ,
isnull(count(case when WEEK = 3 then WEEK end),0) WEEK03 ,
EMPLOYEE
from DETAILTRAN
group by EMPLOYEE
)
select WEEK01, WEEK02, WEEK03, VENDOR, EMPLOYEE = '' from VENDOR
union all
select WEEK01, WEEK02, WEEK03, VENDOR='', EMPLOYEE from EMPLOYEE
SQL FIDDLE DEMO
To update the result to SUMMARTRAN table use this
with VENDOR as
(
select isnull(count(case when WEEK = 1 then WEEK end),0) WEEK01,
isnull(count(case when WEEK = 2 then WEEK end),0) WEEK02 ,
isnull(count(case when WEEK = 3 then WEEK end),0) WEEK03 ,
VENDOR
from DETAILTRAN
group by VENDOR
),EMPLOYEE as
(
select isnull(count(case when WEEK = 1 then WEEK end),0) WEEK01,
isnull(count(case when WEEK = 2 then WEEK end),0) WEEK02 ,
isnull(count(case when WEEK = 3 then WEEK end),0) WEEK03 ,
EMPLOYEE
from DETAILTRAN
group by EMPLOYEE
)
insert into SUMMARTRAN (WEEK01, WEEK02, WEEK03, VENDOR, EMPLOYEE)
select WEEK01, WEEK02, WEEK03, VENDOR, EMPLOYEE = '' from VENDOR
union all
select WEEK01, WEEK02, WEEK03, VENDOR='', EMPLOYEE from EMPLOYEE