return count of true/false in a column of a sql table in c#?
How to return count of true/ false in a column of a table. I have a table in sql containing 5 columns with bollean type. Now I have to return the number of trues and falses in each column and displ开发者_如何学JAVAay on my frontend. Can somebody guide me to write the query?
Thanks
without more info, your query would be something like
select
sum( if( FirstLogicalColumn, 1, 0 ) ) FirstCount,
sum( if( SecondLogicalColumn, 1, 0 ) ) SecondCount,
sum( if( ThirdLogicalColumn, 1, 0 ) ) ThirdCount,
sum( if( FourthLogicalColumn, 1, 0 ) ) FourthCount,
sum( if( FifthLogicalColumn, 1, 0 ) ) FifthCount
from
YourTable
if SQL-Server
select
sum( case when FirstLogicalColumn then 1 else 0 end ) FirstCount,
sum( case when SecondLogicalColumn then 1 else 0 end ) SecondCount,
sum( case when ThirdLogicalColumn then 1 else 0 end ) ThirdCount,
sum( case when FourthLogicalColumn then 1 else 0 end ) FourthCount,
sum( case when FifthLogicalColumn then 1 else 0 end ) FifthCount
from
YourTable
If you wanted grouped by some criteria like a category, date, etc...
select
YourGroupColumn,
sum( other columns per abve )
from
YourTable
group by
YourGroupColumn
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