Conjunctive Queries

Queries may have several terms.

The terms may share variables.

The query is solved in left-to-right order.

The query succeeds only if ALL the terms succeed.

owns( glen , stereo ) .

owns( glen , car ) .

owns( glen , tv ).

type( stereo , machine ) .

type( car , vehicle ) .

type( tv , machine ) .

type( computer , machine ) .

| ? - owns( glen , X ) , type( X , machine ) .

X = stereo ; X = tv ; no

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