SQL Count number of true values from a row then multiply with another column

Question

I am trying to count the number of true values from a row, and so far it's looking good. After I get the value I would like to multiply that with the value from column 'Amount' in the same row.

Table test look like this, type of LA and MD are tinyint (checkbox)

ID   |  Amount |   LA   |   MD
------------------------------------
1    |    7    |   1    |   0
2    |    2    |   1    |   1

So far I can count true values from table test using:

SELECT count(*)
FROM test
WHERE LA = true

But ones I start implementing the multiplication it gets messy, not yet that steady on the syntax. Any tips would be greatly appreciated.

Answer 1

To take the correct result if you have LA=False and MD=True, try

SELECT Amount * (LA + MD)
FROM test
WHERE LA = true
    OR MD = true

Answer 2

According to your last comment, the query should be following

SELECT Amount * (LA + MD)
FROM test