mysql - How can i perform the arithmetic operation in SQL? -

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now want perform arithmetic operation through query.
so, need output (points[1]+points[2]+points[4]-points[3] = result).
example: 50+50+50-150 = 0 points.

so how possible via sql query.

+-------------+-----+ | points_type | sum | +-------------+-----+ |           1 |  50 | |           2 |  50 | |           3 | 150 | |           4 |  50 | +-------------+-----+

you

select sum(sum) - 2 * (select sum tablename points_type = 3) tablename

where tablename name of table





wiki

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