Hey,
I have an SQL exercise, and i have no idea how to solve this.
I have 2 tables.
The first table has 1 record for simplicity and 3 columns (ID, A, . Like this:
Row Number ID A B
1 XY 100 10
The second table has 3 record and 3 columns (ID, a1, Data):
Row Number ID a1 Date
1 XY 30 2018.12.31
2 XY 30 2019.03.31
3 XY 30 2019.06.30
My task to get this table:
Row Number ID A B a1 Date
1 XY 0 10 30 2018.12.31
2 XY 0 0 30 2019.03.31
3 XY 90 0 30 2019.06.30
"A" field has to be 0, except the latest line by date, which has to be the sum of "a1" (3*30).
"B" field has to be 0, except the first line by date, which has to be equal "B" from the first table (10).
Thanks for your support and help.