mysql - Using "All" as a choice to get all the records from database in Crystal Report -

my requirement provide all parameter in crystal report. , when user select all record should displayed without filtering.

there many solution available like:

if {parameter} = "all" true else table.column = {parameter} 

this works fine single parameter all option. in case have multiple parameters , each parameter want give all option , in case using above solution doesn't help. e.g. there 3 params , have used above solution and clause. while running user select all 2 params , value 3rd param still records displaying no filtering happening.