code: func NewSortedBuilder(sc *stmtctx.StatementContext, numBuckets, id int64, tp *types.FieldType) *SortedBuilder {
  	return &SortedBuilder{
  		sc:              sc,
  		numBuckets:      numBuckets,
  		valuesPerBucket: 1,
  		hist:            NewHistogram(id, 0, 0, 0, tp, int(numBuckets), 0),
  	}
  }
docs: // NewSortedBuilder creates a new SortedBuilder.