I want to add two columns in MySql workbench? -


my table name 'bills' want sum of columns electricity , gas , sum should automatically stored in column named total.which trigger can work please tell me correct code.i have searched lot didn't got answer.

electricity+gas=total 1            2   3

sorry, if herrsekurr correct , homework, it's trick question.

tell teacher: "teacher, 1 should never store derived result table. beauty , power in sql ability generate desired query current data."

to so: "select electricity, gas, sum(electricity + gas) your_table"

now, if want index (maybe that's database term meant), accept answer, ask new question...


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