sql - How to join according to value of a field on mysql -


i have user table in database , there user_type field, has 0 or 1. if value 0, want joined teacher table if not student table.

is possible?

you use cross apply or cte dont specify db using should work generic solution

select t1.fields,t2.fields user_table t1 left join teacher_table t2  on t1.id=t2.id  , t1.user_type_field=0 union select t1.fields,t2.fields user_table t1 left join student_table t2  on t1.id=t2.id  , t1.user_type_field=1

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