First of all I want to say sorry if I say or do something wrong because this is my firs time that I ask something. I'm new to sql server so I tried do find out myself but I didn't find something that may help me so this is why I'm here. I have 3 different tables: 

```
1.tbl_Product with ID, Quantity and others;
2.tbl_Type with ID, Name;
3.tbl_Entry_Exit with ID,TypeID,ProductID,Quantity,Price,Total.

```

I want to add or subtract the quantity from `tbl_Product` if `TypeID = 1(Entry) or 2(Subtract) from tbl_Entry_Exit`.
Thank you in advance!