A noun is said to be in dative case if it is the Indirect object of the verb. (Indirect object of the verb is the noun
for whom or for which the action of the verb is carried out). There should not be a preposition before
the indirect object because in that case it will be the object of that preposition.
The teacher gave the students few exercises.
Students is in dative case. It is the indirect object of the verb ‘give.