Method applyPagination

query/query.go:2493–2507

applyPagination applies count and offset to lists inside uidMatrix.

(ctx context.Context)

// applyPagination applies count and offset to lists inside uidMatrix.
func (sg *SubGraph) applyPagination(ctx context.Context) error {
	if sg.Params.Count == 0 && sg.Params.Offset == 0 { // No pagination.
		return nil
	}

	sg.updateUidMatrix()
	for i := range sg.uidMatrix {
		// Apply the offsets.
		start, end := x.PageRange(sg.Params.Count, sg.Params.Offset, len(sg.uidMatrix[i].Uids))
		sg.uidMatrix[i].Uids = sg.uidMatrix[i].Uids[start:end]
	}
	// Re-merge the UID matrix.
	sg.DestUIDs = algo.MergeSorted(sg.uidMatrix)
	return nil
}

// applyOrderAndPagination orders each posting list by a given attribute
// before applying pagination.