How to SUM and SUBTRACT using SQL?

Question

I am using MySQL and I have two tables:

master_table

• ORDERNO
• ITEM
• QTY

stock_bal

Answer 1

An example for subtraction is given below:

Select value1 - (select value2 from AnyTable1) from AnyTable2

value1 & value2 can be count,sum,average output etc. But the values should be comapatible