consider the following relational schema and briefly answer the following questions: emp(eid:integer, ename:string, age:integer, salary:real) works(eid:integer, did:integer, pcttime:integer) dept(did:integer, budget:real, managerid:integer) define an attribute-based constraint on emp that will ensure that every employee makes at most $10,000. define a tuple-based constraint on dept that will ensure that all managers have age > 50. define an assertion on dept that will ensure that all managers have age > 50. compare assertion in (c) with the equivalent tuple-based constraint in (b). explain which is better. define a row-level trigger that no update can reduce employee’s salary
