mysql - select: result based on occurrence of explicit value -


given following mysql table:

create table fonts     (`id` int, `fontname` varchar(22), `price` int,`reducedprice` int,`weight` int) ;  insert fonts     (`id`, `fontname`, `price`,`reducedprice`,`weight`) values     (1, 'regular', 50,30,1),     (2, 'regular-italic', 50,20,1),     (3, 'medium', 60,30,2),     (4, 'medium-italic', 50,30,2),     (5, 'bold', 50,30,3),     (6, 'bold-italic', 50,30,3),     (7, 'bold-condensed', 50,30,3),     (8, 'super', 50,30,4) ;

as example user chooses following ids: 1,2,3,5,6,7 result in following query/result:

> select * fonts id in(1,2,3,5,6,7);  id  fontname        price       reducedprice    weight 1   regular         50          30              1 2   regular-italic  50          20              1 3   medium          60          30              2 5   bold            50          30              3 6   bold-italic     50          30              3 7   bold-condensed  50          30              3

is possible have kind of "if statement" in query return new field based on column weight. value occurs more once reducedprice should returned newprice else price:

id  fontname        price   reducedprice    weight    newprice 1   regular         50      30              1         30 2   regular-italic  50      20              1         20 3   medium          60      30              2         60 5   bold            50      30              3         30 6   bold-italic     50      30              3         30 7   bold-condensed  50      30              3         30

which means ids 1,2,5,6,7 should reduced id 3 not weight "2" occurs once

please find fiddle here: http://sqlfiddle.com/#!9/73f5db/1 , help!

write subquery gets number of occurrences of each weight, , join this. can test number of occurrences decide field put in newprice.

select f.*, if(weight_count = 1, price, reducedprice) newprice fonts f join (select weight, count(*) weight_count       fonts       id in (1, 2, 3, 5, 6, 7)       group weight) w on f.weight = w.weight id in (1, 2, 3, 5, 6, 7)

updated fiddle


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