database - MySQL syntax checking if parameter is null -


i looking way execute mysql statement checking if given parameter exists. remember can following in oracle achieve that: 

select s.* site s  s.study = :study , (:enabled null or s.enabled = :enabled)

is possible in mysql too? same code executes without error never return records.

my goal here avoid multiple lfs , elses in java code. should work way query looks when enabled parameter null:

select s.* site s  s.study = :study

and if parameter not null:

select s.* site s  s.study = :study , s.enabled = :enabled

and want single query

i believe asking:

select s.* site s s.study = "some_study" , (s.enabled null or s.enabled = '' or s.enabled = "enabled");

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