write as follows:
select * from t_user t
where 1 = 1
<if test="id != null and id != """>
and t.id = -sharp{id}
</if>
if id is empty, all users will be found. What should I do?
if the id non-null judgment is made before the call, then the judgment in the mapper file is meaningless, can it be removed?
sincerely ask for advice, thank you ~
since your business requirement is that all queries are not allowed, it is natural to check before the query and delete the non-empty judgment
you can add an else:
this non-empty check is added to the controller bar
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