SQL - Delete Cascade is used with? -

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i'm learning sql , i'm stuck on 1 of review questions , can't find answer in text book. when 'delete cascade'

what 'used' with?

  • a. used primary key constraint
  • b. used unique constraint
  • c. used referential constraint
  • d. used type constraint

i want primary key because going identify correct tuple when cascades? right/wrong, don't know 1 right.

thanks.

it used referential constraint.

more referential constraint


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