SQL Server: Sum values from multiple rows into one row -

i trying sum values multiple rows. example:

my output is:

id  value --------- 1    3 1    4

what see is:

id  value --------- 1   7

this code:

select     id case sum(cast(value float))     when 0 [other_value]     else isnull([value] ,'')     end  'value' table1 id = 1 group id

i saw solutions online such had include group by in order avoid error:

is invalid in select list because not contained in either aggregate function or group clause

but, still no sum.

note: values varchar, therefore, need cast

you trying sum string (even if cast it) query work if isnull goes 0 or numeric value

select id, sum(case when cast(value float) = 0 cast([other_value] float) else isnull([value], 0)  end) 'value' table1 id = 1 group id

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