sql - Adding constraint to a table referencing a subset of records of another table -


say have following tables:

user(user_id, name, age,...) job(job_id, salary, user_id)

i want have constraint on job whenever job's salary > 20,000, user doing job must of age >= 18. have tried check constraint seems work on single table only?

you can user-defined function. function can value in other table.

i'm not recommending approach. many applications, wrap insert/update statements in stored procedure/function , put logic there. however, possible without trigger.


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