SLIMIT/SOFFSET

influxql/ast.go

@@ -1657,22 +1657,22 @@ func (s *SelectStatement) NamesInDimension() []string {
 }
 
 // LimitTagSets returns a tag set list with SLIMIT and SOFFSET applied.
-func (s *SelectStatement) LimitTagSets(a []*TagSet) []*TagSet {
+func LimitTagSets(a []*TagSet, slimit, soffset int) []*TagSet {
 	// Ignore if no limit or offset is specified.
-	if s.SLimit == 0 && s.SOffset == 0 {
+	if slimit == 0 && soffset == 0 {
 		return a
 	}
 
 	// If offset is beyond the number of tag sets then return nil.
-	if s.SOffset > len(a) {
+	if soffset > len(a) {
 		return nil
 	}
 
 	// Clamp limit to the max number of tag sets.
-	if s.SOffset+s.SLimit > len(a) {
-		s.SLimit = len(a) - s.SOffset
+	if soffset+slimit > len(a) {
+		slimit = len(a) - soffset
 	}
-	return a[s.SOffset : s.SOffset+s.SLimit]
+	return a[soffset : soffset+slimit]
 }
 
 // walkNames will walk the Expr and return the database fields

influxql/iterator.go

@@ -475,6 +475,12 @@ type IteratorOptions struct {
 
 	// Sorted in time ascending order if true.
 	Ascending bool
+
+	// Limits the number of points per series.
+	Limit, Offset int
+
+	// Limits the number of series.
+	SLimit, SOffset int
 }
 
 // newIteratorOptionsStmt creates the iterator options from stmt.
@@ -510,6 +516,9 @@ func newIteratorOptionsStmt(stmt *SelectStatement) (opt IteratorOptions, err err
 	opt.Condition = stmt.Condition
 	opt.Ascending = stmt.TimeAscending()
 
+	opt.Limit, opt.Offset = stmt.Limit, stmt.Offset
+	opt.SLimit, opt.SOffset = stmt.SLimit, stmt.SOffset
+
 	return opt, nil
 }
 

tsdb/engine.go

@@ -170,8 +170,8 @@ func newTxVarRefIterator(tx Tx, sh *Shard, opt influxql.IteratorOptions, dimensi
 				return err
 			}
 
-			// FIXME(benbjohnson): Calculate tag sets and apply SLIMIT/SOFFSET.
-			// tagSets = m.stmt.LimitTagSets(tagSets)
+			// Calculate tag sets and apply SLIMIT/SOFFSET.
+			tagSets = influxql.LimitTagSets(tagSets, opt.SLimit, opt.SOffset)
 
 			for _, t := range tagSets {
 				for i, seriesKey := range t.SeriesKeys {