Is there a way to define a variable on a update mysql query? -

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i mean like:

update table_name set field_1=if(date_add(data_field,interval 30 hour) >= now(),1,0), field_2=if(date_add(data_field,interval 30 hour) >= now(),1,0) ...

well in case need use date_add(data_field,interval 30 hour), 2 times, there way store in variable or it? don't need call 2 times.

thanks.

sure:

set @mydate := date_add(data_field,interval 30 hour);  update table_name set field_1=if(@mydate >= now(),1,0),  field_2=if(@mydate >= now(),1,0) ...

fyi, these called user defined variables


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