SQL - MYSQL One query recieving set limit on different column values -


lets have table set of different columns (offcourse),

example : 

table     id    col1 integer(1),   // 0 || 1    col2 // --||--    col3 // --||--    col4 // --||--

is possible, in 1 query select 4 rows col1=1 , select 4 rows col2=1 , select 4 rows col3=1 etc etc. think understand mean.

what have done far make 4 different queries or make 1 query , (col1 = 1 or col2=1 or... etc).

this works if limit result lets 16, might 15 rows col1=1 , maybe 1 row col2=1 , col3,col4 - no result.

so dear fellas; there way in 1 query (i think not)

select * table col1=1 limit 4 union select * table col2=1 limit 4 union select * table col3=1 limit 4 union  select * table col4=1 limit 4

this 1 result 16records max. if there less 4rows certin criteria, you'll less rows. duplicates removed, resulting in less 16 rows. not different rows.

if single row col1=1 , col2=1, might returned twice if use union all, union slower large datasets


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