Where NVL (colom, '@')=NVL (: the column, the '@')
This grammatically correct?
Have a hole?

CodePudding user response:

That depends on what do you mean by like express

CodePudding user response:

See you want to achieve specific effects, such as: the column is empty, will match all colom did not empty,
If colom=: the column, the column is empty, if the result sets 0, namely a don't match (empty does not match the empty),

CodePudding user response:

Whether there is no problem, syntax and the specific business matching, also look at the actual situation,

CodePudding user response:

Is null or empty values should be different bai, this equation has a loophole, if: the column value is @