need a query to get the following two select with one connection to mysql -


i need count(calmness) table entity_epoch_data in mysql twice :

where column of calmness>0 , calmness<0

so connect database twice follow:

select count(calmness) omid.entity_epoch_data calmness<0;  select count(calmness) omid.entity_epoch_data calmness>=0;

i wondering if can combine these 2 query , result 1 table 1 connection?

i tried did not work:

select c1,c2 (  select count(calmness) c1 omid.entity_epoch_data calmness<0,  select count(calmness) c2 omid.entity_epoch_data calmness>=0);

can help?

this can done using sum() expression,when using sum() within expression evaluates true/false i.e 1/0 based on result of expression ,note using aggregate function without grouping them result in single row 

select   sum(calmness < 0) c1,  sum(calmness >= 0)  c2 omid.entity_epoch_data ;

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