sql - Multi-statement query for selecting two rows at a time -


is there way perform sql query search multiple dependent clauses? if had table of humans, want humans of (type = student , id = 1) && (type = teacher , id = 44). can imagine, can expand each bracket multiple statements per bracket , add third, fourth bracket query more types.

the table follows:

humans id type name 

so far, forced call same query many times

select *  t_humans  type = a_type , id = an_id 

if understand correctly, generic sql method use more complex boolean conditions:

select h.* t_humans h (type = 'student' , id = 1) or       (type = 'teacher' , id = 44); 

some databases allow simplify using tuples in:

select h.* t_humans h (type, id) in (('student', 1), ('teacher', 44)); 

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