diff --git a/lib/encoding/float.go b/lib/encoding/float.go
new file mode 100644
index 000000000..c6f1786bc
--- /dev/null
+++ b/lib/encoding/float.go
@@ -0,0 +1,37 @@
+package encoding
+
+import (
+	"sync"
+)
+
+// GetFloat64s returns a slice of float64 values with the given size.
+//
+// When the returned slice is no longer needed, it is advised calling PutFloat64s() on it,
+// so it could be re-used.
+func GetFloat64s(size int) *Float64s {
+	v := float64sPool.Get()
+	if v == nil {
+		v = &Float64s{}
+	}
+	a := v.(*Float64s)
+	if n := size - cap(a.A); n > 0 {
+		a.A = append(a.A[:cap(a.A)], make([]float64, n)...)
+	}
+	a.A = a.A[:size]
+	return a
+}
+
+// PutFloat64s returns a to the pool, so it can be re-used via GetFloat64s.
+//
+// The a cannot be used after returning to the pull.
+func PutFloat64s(a *Float64s) {
+	a.A = a.A[:0]
+	float64sPool.Put(a)
+}
+
+var float64sPool sync.Pool
+
+// Float64s holds an array of float64 values.
+type Float64s struct {
+	A []float64
+}
diff --git a/lib/logstorage/block_search.go b/lib/logstorage/block_search.go
index 0b678be24..94fc1ad07 100644
--- a/lib/logstorage/block_search.go
+++ b/lib/logstorage/block_search.go
@@ -1,6 +1,7 @@
 package logstorage
 
 import (
+	"math"
 	"strconv"
 	"sync"
 	"time"
@@ -274,25 +275,26 @@ func (ih *indexBlockHeader) mustReadBlockHeaders(dst []blockHeader, p *part) []b
 }
 
 type blockResult struct {
-	buf       []byte
+	// buf holds all the bytes behind the requested column values in the block.
+	buf []byte
+
+	// values holds all the requested column values in the block.
 	valuesBuf []string
 
-	// streamID is streamID for the given blockResult
+	// streamID is streamID for the given blockResult.
 	streamID streamID
 
-	// cs contain values for the requested columns.
-	//
-	// The corresponding requested column names are stored at columnsNames.
-	cs []blockResultColumn
-
-	// timestamps contain timestamps for the selected log entries
+	// timestamps contain timestamps for the selected log entries in the block.
 	timestamps []int64
 
-	// columnNamesBuf is used only if all the columns must be fetched.
-	columnNamesBuf []string
+	// csOffset contains cs offset for the requested columns.
+	//
+	// columns with indexes below csOffset are ignored.
+	// This is needed for simplifying data transformations at pipe stages.
+	csOffset int
 
-	// columnNames references the list of names for cs columns.
-	columnNames []string
+	// cs contains requested columns.
+	cs []blockResultColumn
 }
 
 func (br *blockResult) reset() {
@@ -303,65 +305,60 @@ func (br *blockResult) reset() {
 
 	br.streamID.reset()
 
+	br.timestamps = br.timestamps[:0]
+
+	br.csOffset = 0
+
 	cs := br.cs
 	for i := range cs {
 		cs[i].reset()
 	}
 	br.cs = cs[:0]
-
-	br.timestamps = br.timestamps[:0]
-
-	clear(br.columnNamesBuf)
-	br.columnNamesBuf = br.columnNamesBuf[:0]
-
-	br.columnNames = nil
 }
 
 func (br *blockResult) fetchAllColumns(bs *blockSearch, bm *bitmap) {
-	// Add _stream column
-	br.columnNamesBuf = append(br.columnNamesBuf, "_stream")
 	if !br.addStreamColumn(bs) {
 		// Skip the current block, since the associated stream tags are missing.
 		br.reset()
 		return
 	}
 
-	// Add _time column
-	br.columnNamesBuf = append(br.columnNamesBuf, "_time")
 	br.addTimeColumn()
 
 	// Add _msg column
 	v := bs.csh.getConstColumnValue("_msg")
 	if v != "" {
-		br.columnNamesBuf = append(br.columnNamesBuf, "_msg")
-		br.addConstColumn(v)
+		br.addConstColumn("_msg", v)
 	} else if ch := bs.csh.getColumnHeader("_msg"); ch != nil {
-		br.columnNamesBuf = append(br.columnNamesBuf, "_msg")
 		br.addColumn(bs, ch, bm)
+	} else {
+		br.addConstColumn("_msg", "")
 	}
 
+	// Add other const columns
 	for _, cc := range bs.csh.constColumns {
 		if isMsgFieldName(cc.Name) {
 			continue
 		}
-		br.columnNamesBuf = append(br.columnNamesBuf, cc.Name)
-		br.addConstColumn(cc.Value)
+		br.addConstColumn(cc.Name, cc.Value)
 	}
 
+	// Add other non-const columns
 	chs := bs.csh.columnHeaders
 	for i := range chs {
 		ch := &chs[i]
 		if isMsgFieldName(ch.name) {
 			continue
 		}
-		br.columnNamesBuf = append(br.columnNamesBuf, ch.name)
 		br.addColumn(bs, ch, bm)
 	}
-	br.columnNames = br.columnNamesBuf
 }
 
 func (br *blockResult) fetchRequestedColumns(bs *blockSearch, bm *bitmap) {
 	for _, columnName := range bs.bsw.so.resultColumnNames {
+		if columnName == "" {
+			columnName = "_msg"
+		}
 		switch columnName {
 		case "_stream":
 			if !br.addStreamColumn(bs) {
@@ -374,22 +371,14 @@ func (br *blockResult) fetchRequestedColumns(bs *blockSearch, bm *bitmap) {
 		default:
 			v := bs.csh.getConstColumnValue(columnName)
 			if v != "" {
-				br.addConstColumn(v)
-				continue
-			}
-			ch := bs.csh.getColumnHeader(columnName)
-			if ch == nil {
-				br.addConstColumn("")
-			} else {
+				br.addConstColumn(columnName, v)
+			} else if ch := bs.csh.getColumnHeader(columnName); ch != nil {
 				br.addColumn(bs, ch, bm)
+			} else {
+				br.addConstColumn(columnName, "")
 			}
 		}
 	}
-	br.columnNames = bs.bsw.so.resultColumnNames
-}
-
-func (br *blockResult) RowsCount() int {
-	return len(br.timestamps)
 }
 
 func (br *blockResult) mustInit(bs *blockSearch, bm *bitmap) {
@@ -401,13 +390,17 @@ func (br *blockResult) mustInit(bs *blockSearch, bm *bitmap) {
 		// Nothing to initialize for zero matching log entries in the block.
 		return
 	}
-	// Initialize timestamps, since they are used for determining the number of rows in br.RowsCount()
+
+	// Initialize timestamps, since they are required for all the further work with br.
+
 	srcTimestamps := bs.getTimestamps()
 	if bm.areAllBitsSet() {
+		// Fast path - all the rows in the block are selected, so copy all the timestamps without any filtering.
 		br.timestamps = append(br.timestamps[:0], srcTimestamps...)
 		return
 	}
 
+	// Slow path - copy only the needed timestamps to br according to filter results.
 	dstTimestamps := br.timestamps[:0]
 	bm.forEachSetBit(func(idx int) bool {
 		ts := srcTimestamps[idx]
@@ -517,7 +510,12 @@ func (br *blockResult) addColumn(bs *blockSearch, ch *columnHeader, bm *bitmap)
 	}
 	dictValues = valuesBuf[valuesBufLen:]
 
+	name := ch.name
+	if name == "" {
+		name = "_msg"
+	}
 	br.cs = append(br.cs, blockResultColumn{
+		name:          name,
 		valueType:     ch.valueType,
 		dictValues:    dictValues,
 		encodedValues: encodedValues,
@@ -528,6 +526,7 @@ func (br *blockResult) addColumn(bs *blockSearch, ch *columnHeader, bm *bitmap)
 
 func (br *blockResult) addTimeColumn() {
 	br.cs = append(br.cs, blockResultColumn{
+		name:   "_time",
 		isTime: true,
 	})
 }
@@ -551,11 +550,11 @@ func (br *blockResult) addStreamColumn(bs *blockSearch) bool {
 	PutStreamTags(st)
 
 	s := bytesutil.ToUnsafeString(bb.B)
-	br.addConstColumn(s)
+	br.addConstColumn("_stream", s)
 	return true
 }
 
-func (br *blockResult) addConstColumn(value string) {
+func (br *blockResult) addConstColumn(name, value string) {
 	buf := br.buf
 	bufLen := len(buf)
 	buf = append(buf, value...)
@@ -568,17 +567,198 @@ func (br *blockResult) addConstColumn(value string) {
 	br.valuesBuf = valuesBuf
 
 	br.cs = append(br.cs, blockResultColumn{
+		name:          name,
 		isConst:       true,
-		valueType:     valueTypeUnknown,
 		encodedValues: valuesBuf[valuesBufLen:],
 	})
 }
 
-// getColumnValues returns values for the column with the given idx.
+func (br *blockResult) updateColumns(columnNames []string) {
+	if br.areSameColumns(columnNames) {
+		// Fast path - nothing to change.
+		return
+	}
+
+	// Slow path - construct the requested columns
+	cs := br.cs
+	csOffset := len(cs)
+	for _, columnName := range columnNames {
+		c := br.getColumnByName(columnName)
+		cs = append(cs, c)
+	}
+	br.csOffset = csOffset
+	br.cs = cs
+}
+
+func (br *blockResult) areSameColumns(columnNames []string) bool {
+	cs := br.getColumns()
+	if len(cs) != len(columnNames) {
+		return false
+	}
+	for i := range cs {
+		if cs[i].name != columnNames[i] {
+			return false
+		}
+	}
+	return true
+}
+
+func (br *blockResult) getColumnByName(columnName string) blockResultColumn {
+	if columnName == "" {
+		columnName = "_msg"
+	}
+
+	cs := br.getColumns()
+	for i := range cs {
+		if cs[i].name == columnName {
+			return cs[i]
+		}
+	}
+
+	return blockResultColumn{
+		name:          columnName,
+		isConst:       true,
+		encodedValues: getEmptyStrings(1),
+	}
+}
+
+func (br *blockResult) getColumns() []blockResultColumn {
+	return br.cs[br.csOffset:]
+}
+
+func (br *blockResult) skipRows(skipRows int) {
+	br.timestamps = append(br.timestamps[:0], br.timestamps[skipRows:]...)
+	cs := br.getColumns()
+	for i := range cs {
+		c := &cs[i]
+		if c.values != nil {
+			c.values = append(c.values[:0], c.values[skipRows:]...)
+		}
+		if c.isConst {
+			continue
+		}
+		if c.encodedValues != nil {
+			c.encodedValues = append(c.encodedValues[:0], c.encodedValues[skipRows:]...)
+		}
+	}
+}
+
+func (br *blockResult) truncateRows(keepRows int) {
+	br.timestamps = br.timestamps[:keepRows]
+	cs := br.getColumns()
+	for i := range cs {
+		c := &cs[i]
+		if c.values != nil {
+			c.values = c.values[:keepRows]
+		}
+		if c.isConst {
+			continue
+		}
+		if c.encodedValues != nil {
+			c.encodedValues = c.encodedValues[:keepRows]
+		}
+	}
+}
+
+func (br *blockResult) appendColumnValues(dst [][]string, columnNames []string) [][]string {
+	for _, columnName := range columnNames {
+		c := br.getColumnByName(columnName)
+		values := c.getValues(br)
+		dst = append(dst, values)
+	}
+	return dst
+}
+
+type blockResultColumn struct {
+	// name is column name.
+	name string
+
+	// isConst is set to true if the column is const.
+	//
+	// The column value is stored in encodedValues[0]
+	isConst bool
+
+	// isTime is set to true if the column contains _time values.
+	//
+	// The column values are stored in blockResult.timestamps
+	isTime bool
+
+	// valueType is the type of non-cost value
+	valueType valueType
+
+	// dictValues contain dictionary values for valueTypeDict column
+	dictValues []string
+
+	// encodedValues contain encoded values for non-const column
+	encodedValues []string
+
+	// values contain decoded values after getValues() call for the given column
+	values []string
+}
+
+func (c *blockResultColumn) reset() {
+	c.name = ""
+	c.isConst = false
+	c.isTime = false
+	c.valueType = valueTypeUnknown
+	c.dictValues = nil
+	c.encodedValues = nil
+	c.values = nil
+}
+
+// getEncodedValues returns encoded values for the given column.
+//
+// The returned encoded values are valid until br.reset() is called.
+func (c *blockResultColumn) getEncodedValues(br *blockResult) []string {
+	if c.encodedValues != nil {
+		return c.encodedValues
+	}
+
+	if !c.isTime {
+		logger.Panicf("BUG: encodedValues may be missing only for _time column; got %q column", c.name)
+	}
+
+	buf := br.buf
+	valuesBuf := br.valuesBuf
+	valuesBufLen := len(valuesBuf)
+
+	for _, timestamp := range br.timestamps {
+		bufLen := len(buf)
+		buf = encoding.MarshalInt64(buf, timestamp)
+		s := bytesutil.ToUnsafeString(buf[bufLen:])
+		valuesBuf = append(valuesBuf, s)
+	}
+
+	c.encodedValues = valuesBuf[valuesBufLen:]
+
+	br.valuesBuf = valuesBuf
+	br.buf = buf
+
+	return c.encodedValues
+}
+
+// getValueAtRow returns value for the value at the given rowIdx.
+//
+// The returned value is valid until br.reset() is called.
+func (c *blockResultColumn) getValueAtRow(br *blockResult, rowIdx int) string {
+	if c.isConst {
+		// Fast path for const column.
+		return c.encodedValues[0]
+	}
+	if c.values != nil {
+		// Fast path, which avoids call overhead for getValues().
+		return c.values[rowIdx]
+	}
+
+	// Slow path - decode all the values and return the given value.
+	values := c.getValues(br)
+	return values[rowIdx]
+}
+
+// getValues returns values for the given column.
 //
 // The returned values are valid until br.reset() is called.
-func (br *blockResult) getColumnValues(idx int) []string {
-	c := &br.cs[idx]
+func (c *blockResultColumn) getValues(br *blockResult) []string {
 	if c.values != nil {
 		return c.values
 	}
@@ -589,6 +769,13 @@ func (br *blockResult) getColumnValues(idx int) []string {
 
 	if c.isConst {
 		v := c.encodedValues[0]
+		if v == "" {
+			// Fast path - return a slice of empty strings without constructing it.
+			c.values = getEmptyStrings(len(br.timestamps))
+			return c.values
+		}
+
+		// Slower path - construct slice of identical values with the len(br.timestamps)
 		for range br.timestamps {
 			valuesBuf = append(valuesBuf, v)
 		}
@@ -694,35 +881,137 @@ func (br *blockResult) getColumnValues(idx int) []string {
 	return c.values
 }
 
-type blockResultColumn struct {
-	// isConst is set to true if the column is const.
-	//
-	// The column value is stored in encodedValues[0]
-	isConst bool
+func (c *blockResultColumn) getFloatValueAtRow(rowIdx int) float64 {
+	if c.isConst {
+		v := c.encodedValues[0]
+		f, _ := tryParseFloat64(v)
+		return f
+	}
+	if c.isTime {
+		return 0
+	}
 
-	// isTime is set to true if the column contains _time values.
-	//
-	// The column values are stored in blockResult.timestamps
-	isTime bool
-
-	// valueType is the type of non-cost value
-	valueType valueType
-
-	// dictValues contain dictionary values for valueTypeDict column
-	dictValues []string
-
-	// encodedValues contain encoded values for non-const column
-	encodedValues []string
-
-	// values contain decoded values after getColumnValues() call for the given column
-	values []string
+	switch c.valueType {
+	case valueTypeString:
+		f, _ := tryParseFloat64(c.encodedValues[rowIdx])
+		return f
+	case valueTypeDict:
+		dictIdx := c.encodedValues[rowIdx][0]
+		f, _ := tryParseFloat64(c.dictValues[dictIdx])
+		return f
+	case valueTypeUint8:
+		return float64(c.encodedValues[rowIdx][0])
+	case valueTypeUint16:
+		b := bytesutil.ToUnsafeBytes(c.encodedValues[rowIdx])
+		return float64(encoding.UnmarshalUint16(b))
+	case valueTypeUint32:
+		b := bytesutil.ToUnsafeBytes(c.encodedValues[rowIdx])
+		return float64(encoding.UnmarshalUint32(b))
+	case valueTypeUint64:
+		b := bytesutil.ToUnsafeBytes(c.encodedValues[rowIdx])
+		return float64(encoding.UnmarshalUint64(b))
+	case valueTypeFloat64:
+		b := bytesutil.ToUnsafeBytes(c.encodedValues[rowIdx])
+		n := encoding.UnmarshalUint64(b)
+		return math.Float64frombits(n)
+	case valueTypeIPv4:
+		return 0
+	case valueTypeTimestampISO8601:
+		return 0
+	default:
+		logger.Panicf("BUG: unknown valueType=%d", c.valueType)
+		return 0
+	}
 }
 
-func (c *blockResultColumn) reset() {
-	c.isConst = false
-	c.isTime = false
-	c.valueType = valueTypeUnknown
-	c.dictValues = nil
-	c.encodedValues = nil
-	c.values = nil
+func (c *blockResultColumn) sumValues(br *blockResult) float64 {
+	if c.isConst {
+		v := c.encodedValues[0]
+		f, _ := tryParseFloat64(v)
+		if f == 0 || math.IsNaN(f) {
+			return 0
+		}
+		return f * float64(len(br.timestamps))
+	}
+	if c.isTime {
+		return 0
+	}
+
+	switch c.valueType {
+	case valueTypeString:
+		sum := float64(0)
+		f := float64(0)
+		values := c.encodedValues
+		for i := range values {
+			if i == 0 || values[i-1] != values[i] {
+				f, _ = tryParseFloat64(values[i])
+			}
+			if !math.IsNaN(f) {
+				sum += f
+			}
+		}
+		return sum
+	case valueTypeDict:
+		a := encoding.GetFloat64s(len(c.dictValues))
+		dictValuesFloat := a.A
+		for i, v := range c.dictValues {
+			f, _ := tryParseFloat64(v)
+			if math.IsNaN(f) {
+				f = 0
+			}
+			dictValuesFloat[i] = f
+		}
+		sum := float64(0)
+		for _, v := range c.encodedValues {
+			dictIdx := v[0]
+			sum += dictValuesFloat[dictIdx]
+		}
+		encoding.PutFloat64s(a)
+		return sum
+	case valueTypeUint8:
+		sum := uint64(0)
+		for _, v := range c.encodedValues {
+			sum += uint64(v[0])
+		}
+		return float64(sum)
+	case valueTypeUint16:
+		sum := uint64(0)
+		for _, v := range c.encodedValues {
+			b := bytesutil.ToUnsafeBytes(v)
+			sum += uint64(encoding.UnmarshalUint16(b))
+		}
+		return float64(sum)
+	case valueTypeUint32:
+		sum := uint64(0)
+		for _, v := range c.encodedValues {
+			b := bytesutil.ToUnsafeBytes(v)
+			sum += uint64(encoding.UnmarshalUint32(b))
+		}
+		return float64(sum)
+	case valueTypeUint64:
+		sum := float64(0)
+		for _, v := range c.encodedValues {
+			b := bytesutil.ToUnsafeBytes(v)
+			sum += float64(encoding.UnmarshalUint64(b))
+		}
+		return sum
+	case valueTypeFloat64:
+		sum := float64(0)
+		for _, v := range c.encodedValues {
+			b := bytesutil.ToUnsafeBytes(v)
+			n := encoding.UnmarshalUint64(b)
+			f := math.Float64frombits(n)
+			if !math.IsNaN(f) {
+				sum += f
+			}
+		}
+		return sum
+	case valueTypeIPv4:
+		return 0
+	case valueTypeTimestampISO8601:
+		return 0
+	default:
+		logger.Panicf("BUG: unknown valueType=%d", c.valueType)
+		return 0
+	}
 }
diff --git a/lib/logstorage/filter_test.go b/lib/logstorage/filter_test.go
index 585099f5a..e05792d11 100644
--- a/lib/logstorage/filter_test.go
+++ b/lib/logstorage/filter_test.go
@@ -203,10 +203,11 @@ func testFilterMatchForStorage(t *testing.T, s *Storage, tenantID TenantID, f fi
 		}
 
 		// Verify columns
-		if len(br.cs) != 1 {
-			t.Fatalf("unexpected number of columns in blockResult; got %d; want 1", len(br.cs))
+		cs := br.getColumns()
+		if len(cs) != 1 {
+			t.Fatalf("unexpected number of columns in blockResult; got %d; want 1", len(cs))
 		}
-		results := br.getColumnValues(0)
+		results := cs[0].getValues(br)
 		if !reflect.DeepEqual(results, expectedResults) {
 			t.Fatalf("unexpected results matched;\ngot\n%q\nwant\n%q", results, expectedResults)
 		}
diff --git a/lib/logstorage/pipe.go b/lib/logstorage/pipe.go
index e08e57734..a286e1c1c 100644
--- a/lib/logstorage/pipe.go
+++ b/lib/logstorage/pipe.go
@@ -27,13 +27,13 @@ type pipeProcessor interface {
 	// The workerID is the id of the worker goroutine, which calls the writeBlock.
 	// It is in the range 0 ... workersCount-1 .
 	//
-	// It is forbidden to hold references to columns after returning from writeBlock, since the caller re-uses columns.
+	// It is forbidden to hold references br after returning from writeBlock, since the caller re-uses it.
 	//
 	// If any error occurs at writeBlock, then cancel() must be called by pipeProcessor in order to notify worker goroutines
 	// to stop sending new data. The occurred error must be returned from flush().
 	//
 	// cancel() may be called also when the pipeProcessor decides to stop accepting new data, even if there is no any error.
-	writeBlock(workerID uint, timestamps []int64, columns []BlockColumn)
+	writeBlock(workerID uint, br *blockResult)
 
 	// flush must flush all the data accumulated in the pipeProcessor to the base pipeProcessor.
 	//
@@ -43,14 +43,14 @@ type pipeProcessor interface {
 	flush() error
 }
 
-type defaultPipeProcessor func(workerID uint, timestamps []int64, columns []BlockColumn)
+type defaultPipeProcessor func(workerID uint, br *blockResult)
 
-func newDefaultPipeProcessor(writeBlock func(workerID uint, timestamps []int64, columns []BlockColumn)) pipeProcessor {
+func newDefaultPipeProcessor(writeBlock func(workerID uint, br *blockResult)) pipeProcessor {
 	return defaultPipeProcessor(writeBlock)
 }
 
-func (dpp defaultPipeProcessor) writeBlock(workerID uint, timestamps []int64, columns []BlockColumn) {
-	dpp(workerID, timestamps, columns)
+func (dpp defaultPipeProcessor) writeBlock(workerID uint, br *blockResult) {
+	dpp(workerID, br)
 }
 
 func (dpp defaultPipeProcessor) flush() error {
diff --git a/lib/logstorage/pipe_fields.go b/lib/logstorage/pipe_fields.go
index 3d9c339c2..3822e2bff 100644
--- a/lib/logstorage/pipe_fields.go
+++ b/lib/logstorage/pipe_fields.go
@@ -34,26 +34,11 @@ type pipeFieldsProcessor struct {
 	ppBase pipeProcessor
 }
 
-func (fpp *pipeFieldsProcessor) writeBlock(workerID uint, timestamps []int64, columns []BlockColumn) {
-	if fpp.pf.containsStar || areSameBlockColumns(columns, fpp.pf.fields) {
-		// Fast path - there is no need in additional transformations before writing the block to ppBase.
-		fpp.ppBase.writeBlock(workerID, timestamps, columns)
-		return
+func (fpp *pipeFieldsProcessor) writeBlock(workerID uint, br *blockResult) {
+	if !fpp.pf.containsStar {
+		br.updateColumns(fpp.pf.fields)
 	}
-
-	// Slow path - construct columns for fpp.pf.fields before writing them to ppBase.
-	brs := getBlockRows()
-	cs := brs.cs
-	for _, f := range fpp.pf.fields {
-		values := getBlockColumnValues(columns, f, len(timestamps))
-		cs = append(cs, BlockColumn{
-			Name:   f,
-			Values: values,
-		})
-	}
-	fpp.ppBase.writeBlock(workerID, timestamps, cs)
-	brs.cs = cs
-	putBlockRows(brs)
+	fpp.ppBase.writeBlock(workerID, br)
 }
 
 func (fpp *pipeFieldsProcessor) flush() error {
diff --git a/lib/logstorage/pipe_head.go b/lib/logstorage/pipe_head.go
index 698c75f33..3eda2ca83 100644
--- a/lib/logstorage/pipe_head.go
+++ b/lib/logstorage/pipe_head.go
@@ -33,31 +33,25 @@ type pipeHeadProcessor struct {
 	rowsProcessed atomic.Uint64
 }
 
-func (hpp *pipeHeadProcessor) writeBlock(workerID uint, timestamps []int64, columns []BlockColumn) {
-	rowsProcessed := hpp.rowsProcessed.Add(uint64(len(timestamps)))
+func (hpp *pipeHeadProcessor) writeBlock(workerID uint, br *blockResult) {
+	rowsProcessed := hpp.rowsProcessed.Add(uint64(len(br.timestamps)))
 	if rowsProcessed <= hpp.ph.n {
 		// Fast path - write all the rows to ppBase.
-		hpp.ppBase.writeBlock(workerID, timestamps, columns)
+		hpp.ppBase.writeBlock(workerID, br)
 		return
 	}
 
 	// Slow path - overflow. Write the remaining rows if needed.
-	rowsProcessed -= uint64(len(timestamps))
+	rowsProcessed -= uint64(len(br.timestamps))
 	if rowsProcessed >= hpp.ph.n {
 		// Nothing to write. There is no need in cancel() call, since it has been called by another goroutine.
 		return
 	}
 
 	// Write remaining rows.
-	rowsRemaining := hpp.ph.n - rowsProcessed
-	cs := make([]BlockColumn, len(columns))
-	for i, c := range columns {
-		cDst := &cs[i]
-		cDst.Name = c.Name
-		cDst.Values = c.Values[:rowsRemaining]
-	}
-	timestamps = timestamps[:rowsRemaining]
-	hpp.ppBase.writeBlock(workerID, timestamps, cs)
+	keepRows := hpp.ph.n - rowsProcessed
+	br.truncateRows(int(keepRows))
+	hpp.ppBase.writeBlock(workerID, br)
 
 	// Notify the caller that it should stop passing more data to writeBlock().
 	hpp.cancel()
diff --git a/lib/logstorage/pipe_skip.go b/lib/logstorage/pipe_skip.go
index d2cf71495..7df995376 100644
--- a/lib/logstorage/pipe_skip.go
+++ b/lib/logstorage/pipe_skip.go
@@ -27,27 +27,21 @@ type pipeSkipProcessor struct {
 	rowsProcessed atomic.Uint64
 }
 
-func (spp *pipeSkipProcessor) writeBlock(workerID uint, timestamps []int64, columns []BlockColumn) {
-	rowsProcessed := spp.rowsProcessed.Add(uint64(len(timestamps)))
+func (spp *pipeSkipProcessor) writeBlock(workerID uint, br *blockResult) {
+	rowsProcessed := spp.rowsProcessed.Add(uint64(len(br.timestamps)))
 	if rowsProcessed <= spp.ps.n {
 		return
 	}
 
-	rowsProcessed -= uint64(len(timestamps))
+	rowsProcessed -= uint64(len(br.timestamps))
 	if rowsProcessed >= spp.ps.n {
-		spp.ppBase.writeBlock(workerID, timestamps, columns)
+		spp.ppBase.writeBlock(workerID, br)
 		return
 	}
 
-	rowsRemaining := spp.ps.n - rowsProcessed
-	cs := make([]BlockColumn, len(columns))
-	for i, c := range columns {
-		cDst := &cs[i]
-		cDst.Name = c.Name
-		cDst.Values = c.Values[rowsRemaining:]
-	}
-	timestamps = timestamps[rowsRemaining:]
-	spp.ppBase.writeBlock(workerID, timestamps, cs)
+	rowsSkip := spp.ps.n - rowsProcessed
+	br.skipRows(int(rowsSkip))
+	spp.ppBase.writeBlock(workerID, br)
 }
 
 func (spp *pipeSkipProcessor) flush() error {
diff --git a/lib/logstorage/pipe_stats.go b/lib/logstorage/pipe_stats.go
index 25dfc6620..b42d1031b 100644
--- a/lib/logstorage/pipe_stats.go
+++ b/lib/logstorage/pipe_stats.go
@@ -35,15 +35,15 @@ type statsFunc interface {
 // All the statsProcessor methods are called from a single goroutine at a time,
 // so there is no need in the internal synchronization.
 type statsProcessor interface {
-	// updateStatsForAllRows must update statsProcessor stats from all the rows.
+	// updateStatsForAllRows must update statsProcessor stats for all the rows in br.
 	//
-	// It must return the increase of internal state size in bytes for the statsProcessor.
-	updateStatsForAllRows(timestamps []int64, columns []BlockColumn) int
+	// It must return the change of internal state size in bytes for the statsProcessor.
+	updateStatsForAllRows(br *blockResult) int
 
-	// updateStatsForRow must update statsProcessor stats from the row at rowIndex.
+	// updateStatsForRow must update statsProcessor stats for the row at rowIndex in br.
 	//
-	// It must return the increase of internal state size in bytes for the statsProcessor.
-	updateStatsForRow(timestamps []int64, columns []BlockColumn, rowIndex int) int
+	// It must return the change of internal state size in bytes for the statsProcessor.
+	updateStatsForRow(br *blockResult, rowIndex int) int
 
 	// mergeState must merge sfp state into statsProcessor state.
 	mergeState(sfp statsProcessor)
@@ -149,7 +149,7 @@ type pipeStatsGroup struct {
 	sfps []statsProcessor
 }
 
-func (spp *pipeStatsProcessor) writeBlock(workerID uint, timestamps []int64, columns []BlockColumn) {
+func (spp *pipeStatsProcessor) writeBlock(workerID uint, br *blockResult) {
 	shard := &spp.shards[workerID]
 
 	for shard.stateSizeBudget < 0 {
@@ -170,60 +170,69 @@ func (spp *pipeStatsProcessor) writeBlock(workerID uint, timestamps []int64, col
 	if len(byFields) == 0 {
 		// Fast path - pass all the rows to a single group with empty key.
 		for _, sfp := range shard.getStatsProcessors(nil) {
-			shard.stateSizeBudget -= sfp.updateStatsForAllRows(timestamps, columns)
+			shard.stateSizeBudget -= sfp.updateStatsForAllRows(br)
 		}
 		return
 	}
 	if len(byFields) == 1 {
 		// Special case for grouping by a single column.
-		values := getBlockColumnValues(columns, byFields[0], len(timestamps))
-		if isConstValue(values) {
+		c := br.getColumnByName(byFields[0])
+		if c.isConst {
 			// Fast path for column with constant value.
-			shard.keyBuf = encoding.MarshalBytes(shard.keyBuf[:0], bytesutil.ToUnsafeBytes(values[0]))
+			shard.keyBuf = encoding.MarshalBytes(shard.keyBuf[:0], bytesutil.ToUnsafeBytes(c.encodedValues[0]))
 			for _, sfp := range shard.getStatsProcessors(shard.keyBuf) {
-				shard.stateSizeBudget -= sfp.updateStatsForAllRows(timestamps, columns)
+				shard.stateSizeBudget -= sfp.updateStatsForAllRows(br)
 			}
 			return
 		}
 
 		// Slower path for column with different values.
+		values := c.getValues(br)
 		var sfps []statsProcessor
-		keyBuf := shard.keyBuf
-		for i := range timestamps {
+		keyBuf := shard.keyBuf[:0]
+		for i := range br.timestamps {
 			if i <= 0 || values[i-1] != values[i] {
 				keyBuf = encoding.MarshalBytes(keyBuf[:0], bytesutil.ToUnsafeBytes(values[i]))
 				sfps = shard.getStatsProcessors(keyBuf)
 			}
 			for _, sfp := range sfps {
-				shard.stateSizeBudget -= sfp.updateStatsForRow(timestamps, columns, i)
+				shard.stateSizeBudget -= sfp.updateStatsForRow(br, i)
 			}
 		}
 		shard.keyBuf = keyBuf
 		return
 	}
 
-	// Pre-calculate column values for byFields in order to speed up building group key in the loop below.
-	shard.columnValues = appendBlockColumnValues(shard.columnValues[:0], columns, byFields, len(timestamps))
-	columnValues := shard.columnValues
+	// Verify whether all the 'by (...)' columns are constant.
+	areAllConstColumns := true
+	keyBuf := shard.keyBuf[:0]
+	for _, f := range byFields {
+		c := br.getColumnByName(f)
+		if !c.isConst {
+			areAllConstColumns = false
+			break
+		}
+		keyBuf = encoding.MarshalBytes(keyBuf, bytesutil.ToUnsafeBytes(c.encodedValues[0]))
+	}
+	shard.keyBuf = keyBuf
 
-	if areConstValues(columnValues) {
-		// Fast path for columns with constant values.
-		keyBuf := shard.keyBuf[:0]
-		for _, values := range columnValues {
-			keyBuf = encoding.MarshalBytes(keyBuf, bytesutil.ToUnsafeBytes(values[0]))
-		}
+	if areAllConstColumns {
+		// Fast path for constant 'by (...)' columns.
 		for _, sfp := range shard.getStatsProcessors(keyBuf) {
-			shard.stateSizeBudget -= sfp.updateStatsForAllRows(timestamps, columns)
+			shard.stateSizeBudget -= sfp.updateStatsForAllRows(br)
 		}
-		shard.keyBuf = keyBuf
 		return
 	}
 
-	// The slowest path - group by multiple columns.
+	// The slowest path - group by multiple columns with different values across rows.
+
+	// Pre-calculate column values for byFields in order to speed up building group key in the loop below.
+	shard.columnValues = br.appendColumnValues(shard.columnValues[:0], byFields)
+	columnValues := shard.columnValues
+
 	var sfps []statsProcessor
-	keyBuf := shard.keyBuf
-	for i := range timestamps {
-		// verify whether the key for 'by (...)' fields equals the previous key
+	for i := range br.timestamps {
+		// Verify whether the key for 'by (...)' fields equals the previous key
 		sameValue := sfps != nil
 		for _, values := range columnValues {
 			if i <= 0 || values[i-1] != values[i] {
@@ -240,35 +249,12 @@ func (spp *pipeStatsProcessor) writeBlock(workerID uint, timestamps []int64, col
 			sfps = shard.getStatsProcessors(keyBuf)
 		}
 		for _, sfp := range sfps {
-			shard.stateSizeBudget -= sfp.updateStatsForRow(timestamps, columns, i)
+			shard.stateSizeBudget -= sfp.updateStatsForRow(br, i)
 		}
 	}
 	shard.keyBuf = keyBuf
 }
 
-func areConstValues(valuess [][]string) bool {
-	for _, values := range valuess {
-		if !isConstValue(values) {
-			return false
-		}
-	}
-	return true
-}
-
-func isConstValue(values []string) bool {
-	if len(values) == 0 {
-		// Return false, since it is impossible to get values[0] value from empty values.
-		return false
-	}
-	vFirst := values[0]
-	for _, v := range values[1:] {
-		if v != vFirst {
-			return false
-		}
-	}
-	return true
-}
-
 func (spp *pipeStatsProcessor) flush() error {
 	if n := spp.stateSizeBudget.Load(); n <= 0 {
 		return fmt.Errorf("cannot calculate [%s], since it requires more than %dMB of memory", spp.ps.String(), spp.maxStateSize/(1<<20))
@@ -282,7 +268,7 @@ func (spp *pipeStatsProcessor) flush() error {
 		shard := &shards[i]
 		for key, spg := range shard.m {
 			// shard.m may be quite big, so this loop can take a lot of time and CPU.
-			// Stop processing data as soon as stopCh is closed without wasting CPU time.
+			// Stop processing data as soon as stopCh is closed without wasting additional CPU time.
 			select {
 			case <-spp.stopCh:
 				return nil
@@ -309,10 +295,10 @@ func (spp *pipeStatsProcessor) flush() error {
 	}
 
 	var values []string
-	var columns []BlockColumn
+	var br blockResult
 	for key, spg := range m {
 		// m may be quite big, so this loop can take a lot of time and CPU.
-		// Stop processing data as soon as stopCh is closed without wasting CPU time.
+		// Stop processing data as soon as stopCh is closed without wasting additional CPU time.
 		select {
 		case <-spp.stopCh:
 			return nil
@@ -334,24 +320,20 @@ func (spp *pipeStatsProcessor) flush() error {
 			logger.Panicf("BUG: unexpected number of values decoded from keyBuf; got %d; want %d", len(values), len(byFields))
 		}
 
+		br.reset()
+
 		// construct columns for byFields
-		columns = columns[:0]
 		for i, f := range byFields {
-			columns = append(columns, BlockColumn{
-				Name:   f,
-				Values: values[i : i+1],
-			})
+			br.addConstColumn(f, values[i])
 		}
 
 		// construct columns for stats functions
 		for _, sfp := range spg.sfps {
 			name, value := sfp.finalizeStats()
-			columns = append(columns, BlockColumn{
-				Name:   name,
-				Values: []string{value},
-			})
+			br.addConstColumn(name, value)
 		}
-		spp.ppBase.writeBlock(0, []int64{0}, columns)
+
+		spp.ppBase.writeBlock(0, &br)
 	}
 
 	return nil
diff --git a/lib/logstorage/stats_count.go b/lib/logstorage/stats_count.go
index 7c96cd4b0..04469c5bb 100644
--- a/lib/logstorage/stats_count.go
+++ b/lib/logstorage/stats_count.go
@@ -5,6 +5,8 @@ import (
 	"slices"
 	"strconv"
 	"unsafe"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 )
 
 type statsCount struct {
@@ -35,49 +37,149 @@ type statsCountProcessor struct {
 	rowsCount uint64
 }
 
-func (scp *statsCountProcessor) updateStatsForAllRows(timestamps []int64, columns []BlockColumn) int {
+func (scp *statsCountProcessor) updateStatsForAllRows(br *blockResult) int {
 	fields := scp.sc.fields
 	if len(fields) == 0 || scp.sc.containsStar {
-		// Fast path - count all the columns.
-		scp.rowsCount += uint64(len(timestamps))
+		// Fast path - unconditionally count all the columns.
+		scp.rowsCount += uint64(len(br.timestamps))
 		return 0
 	}
+	if len(fields) == 1 {
+		// Fast path for count(single_column)
+		c := br.getColumnByName(fields[0])
+		if c.isConst {
+			if c.encodedValues[0] != "" {
+				scp.rowsCount += uint64(len(br.timestamps))
+			}
+			return 0
+		}
+		if c.isTime {
+			scp.rowsCount += uint64(len(br.timestamps))
+			return 0
+		}
+		switch c.valueType {
+		case valueTypeString:
+			for _, v := range c.encodedValues {
+				if v != "" {
+					scp.rowsCount++
+				}
+			}
+			return 0
+		case valueTypeDict:
+			zeroDictIdx := slices.Index(c.dictValues, "")
+			if zeroDictIdx < 0 {
+				scp.rowsCount += uint64(len(br.timestamps))
+				return 0
+			}
+			for _, v := range c.encodedValues {
+				if int(v[0]) != zeroDictIdx {
+					scp.rowsCount++
+				}
+			}
+			return 0
+		case valueTypeUint8, valueTypeUint16, valueTypeUint32, valueTypeUint64, valueTypeFloat64, valueTypeIPv4, valueTypeTimestampISO8601:
+			scp.rowsCount += uint64(len(br.timestamps))
+			return 0
+		default:
+			logger.Panicf("BUG: unknown valueType=%d", c.valueType)
+			return 0
+		}
+	}
 
 	// Slow path - count rows containing at least a single non-empty value for the fields enumerated inside count().
-	bm := getBitmap(len(timestamps))
+	bm := getBitmap(len(br.timestamps))
 	defer putBitmap(bm)
 
 	bm.setBits()
 	for _, f := range fields {
-		if idx := getBlockColumnIndex(columns, f); idx >= 0 {
-			values := columns[idx].Values
+		c := br.getColumnByName(f)
+		if c.isConst {
+			if c.encodedValues[0] != "" {
+				scp.rowsCount += uint64(len(br.timestamps))
+				return 0
+			}
+			continue
+		}
+		if c.isTime {
+			scp.rowsCount += uint64(len(br.timestamps))
+			return 0
+		}
+		switch c.valueType {
+		case valueTypeString:
 			bm.forEachSetBit(func(i int) bool {
-				return values[i] == ""
+				return c.encodedValues[i] == ""
 			})
+		case valueTypeDict:
+			if !slices.Contains(c.dictValues, "") {
+				scp.rowsCount += uint64(len(br.timestamps))
+				return 0
+			}
+			bm.forEachSetBit(func(i int) bool {
+				dictIdx := c.encodedValues[i][0]
+				return c.dictValues[dictIdx] == ""
+			})
+		case valueTypeUint8, valueTypeUint16, valueTypeUint32, valueTypeUint64, valueTypeFloat64, valueTypeIPv4, valueTypeTimestampISO8601:
+			scp.rowsCount += uint64(len(br.timestamps))
+			return 0
+		default:
+			logger.Panicf("BUG: unknown valueType=%d", c.valueType)
+			return 0
 		}
 	}
 
-	emptyValues := 0
+	scp.rowsCount += uint64(len(br.timestamps))
 	bm.forEachSetBit(func(i int) bool {
-		emptyValues++
+		scp.rowsCount--
 		return true
 	})
-
-	scp.rowsCount += uint64(len(timestamps) - emptyValues)
 	return 0
 }
 
-func (scp *statsCountProcessor) updateStatsForRow(_ []int64, columns []BlockColumn, rowIdx int) int {
+func (scp *statsCountProcessor) updateStatsForRow(br *blockResult, rowIdx int) int {
 	fields := scp.sc.fields
 	if len(fields) == 0 || scp.sc.containsStar {
-		// Fast path - count the given column
+		// Fast path - unconditionally count the given column
 		scp.rowsCount++
 		return 0
 	}
+	if len(fields) == 1 {
+		// Fast path for count(single_column)
+		c := br.getColumnByName(fields[0])
+		if c.isConst {
+			if c.encodedValues[0] != "" {
+				scp.rowsCount++
+			}
+			return 0
+		}
+		if c.isTime {
+			scp.rowsCount++
+			return 0
+		}
+		switch c.valueType {
+		case valueTypeString:
+			if v := c.encodedValues[rowIdx]; v != "" {
+				scp.rowsCount++
+			}
+			return 0
+		case valueTypeDict:
+			dictIdx := c.encodedValues[rowIdx][0]
+			if v := c.dictValues[dictIdx]; v != "" {
+				scp.rowsCount++
+			}
+			return 0
+		case valueTypeUint8, valueTypeUint16, valueTypeUint32, valueTypeUint64, valueTypeFloat64, valueTypeIPv4, valueTypeTimestampISO8601:
+			scp.rowsCount++
+			return 0
+		default:
+			logger.Panicf("BUG: unknown valueType=%d", c.valueType)
+			return 0
+		}
+	}
 
 	// Slow path - count the row at rowIdx if at least a single field enumerated inside count() is non-empty
 	for _, f := range fields {
-		if idx := getBlockColumnIndex(columns, f); idx >= 0 && columns[idx].Values[rowIdx] != "" {
+		c := br.getColumnByName(f)
+		if v := c.getValueAtRow(br, rowIdx); v != "" {
 			scp.rowsCount++
 			return 0
 		}
diff --git a/lib/logstorage/stats_sum.go b/lib/logstorage/stats_sum.go
index 0ee7b32e6..4ab3dcb64 100644
--- a/lib/logstorage/stats_sum.go
+++ b/lib/logstorage/stats_sum.go
@@ -35,46 +35,28 @@ type statsSumProcessor struct {
 	sum float64
 }
 
-func (ssp *statsSumProcessor) updateStatsForAllRows(timestamps []int64, columns []BlockColumn) int {
+func (ssp *statsSumProcessor) updateStatsForAllRows(br *blockResult) int {
 	if ssp.ss.containsStar {
 		// Sum all the columns
-		for _, c := range columns {
-			ssp.sum += sumValues(c.Values)
+		for _, c := range br.getColumns() {
+			ssp.sum += c.sumValues(br)
 		}
 		return 0
 	}
 
 	// Sum the requested columns
 	for _, field := range ssp.ss.fields {
-		if idx := getBlockColumnIndex(columns, field); idx >= 0 {
-			ssp.sum += sumValues(columns[idx].Values)
-		}
+		c := br.getColumnByName(field)
+		ssp.sum += c.sumValues(br)
 	}
 	return 0
 }
 
-func sumValues(values []string) float64 {
-	sum := float64(0)
-	f := float64(0)
-	for i, v := range values {
-		if i == 0 || values[i-1] != v {
-			f, _ = tryParseFloat64(v)
-			if math.IsNaN(f) {
-				// Ignore NaN values, since this is the expected behaviour by most users.
-				f = 0
-			}
-		}
-		sum += f
-	}
-	return sum
-}
-
-func (ssp *statsSumProcessor) updateStatsForRow(_ []int64, columns []BlockColumn, rowIdx int) int {
+func (ssp *statsSumProcessor) updateStatsForRow(br *blockResult, rowIdx int) int {
 	if ssp.ss.containsStar {
 		// Sum all the fields for the given row
-		for _, c := range columns {
-			v := c.Values[rowIdx]
-			f, _ := tryParseFloat64(v)
+		for _, c := range br.getColumns() {
+			f := c.getFloatValueAtRow(rowIdx)
 			if !math.IsNaN(f) {
 				ssp.sum += f
 			}
@@ -84,12 +66,10 @@ func (ssp *statsSumProcessor) updateStatsForRow(_ []int64, columns []BlockColumn
 
 	// Sum only the given fields for the given row
 	for _, field := range ssp.ss.fields {
-		if idx := getBlockColumnIndex(columns, field); idx >= 0 {
-			v := columns[idx].Values[rowIdx]
-			f, _ := tryParseFloat64(v)
-			if !math.IsNaN(f) {
-				ssp.sum += f
-			}
+		c := br.getColumnByName(field)
+		f := c.getFloatValueAtRow(rowIdx)
+		if !math.IsNaN(f) {
+			ssp.sum += f
 		}
 	}
 	return 0
diff --git a/lib/logstorage/stats_unique.go b/lib/logstorage/stats_unique.go
index 265841f5d..721cbd53a 100644
--- a/lib/logstorage/stats_unique.go
+++ b/lib/logstorage/stats_unique.go
@@ -4,7 +4,6 @@ import (
 	"fmt"
 	"slices"
 	"strconv"
-	"strings"
 	"unsafe"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
@@ -43,36 +42,38 @@ type statsUniqProcessor struct {
 	keyBuf       []byte
 }
 
-func (sup *statsUniqProcessor) updateStatsForAllRows(timestamps []int64, columns []BlockColumn) int {
+func (sup *statsUniqProcessor) updateStatsForAllRows(br *blockResult) int {
 	fields := sup.su.fields
 	m := sup.m
 
 	stateSizeIncrease := 0
 	if len(fields) == 0 || sup.su.containsStar {
 		// Count unique rows
-		keyBuf := sup.keyBuf
-		for i := range timestamps {
+		columns := br.getColumns()
+		keyBuf := sup.keyBuf[:0]
+		for i := range br.timestamps {
 			seenKey := true
 			for _, c := range columns {
-				values := c.Values
+				values := c.getValues(br)
 				if i == 0 || values[i-1] != values[i] {
 					seenKey = false
 					break
 				}
 			}
 			if seenKey {
+				// This key has been already counted.
 				continue
 			}
 
 			allEmptyValues := true
 			keyBuf = keyBuf[:0]
 			for _, c := range columns {
-				v := c.Values[i]
+				v := c.getValueAtRow(br, i)
 				if v != "" {
 					allEmptyValues = false
 				}
 				// Put column name into key, since every block can contain different set of columns for '*' selector.
-				keyBuf = encoding.MarshalBytes(keyBuf, bytesutil.ToUnsafeBytes(c.Name))
+				keyBuf = encoding.MarshalBytes(keyBuf, bytesutil.ToUnsafeBytes(c.name))
 				keyBuf = encoding.MarshalBytes(keyBuf, bytesutil.ToUnsafeBytes(v))
 			}
 			if allEmptyValues {
@@ -88,39 +89,103 @@ func (sup *statsUniqProcessor) updateStatsForAllRows(timestamps []int64, columns
 		return stateSizeIncrease
 	}
 	if len(fields) == 1 {
-		// Fast path for a single column
-		if idx := getBlockColumnIndex(columns, fields[0]); idx >= 0 {
-			values := columns[idx].Values
-			for i, v := range values {
+		// Fast path for a single column.
+		// The unique key is formed as "<is_time> <value_type>? <encodedValue>",
+		// where <value_type> is skipped if <is_time> == 1.
+		// This guarantees that keys do not clash for different column types acorss blocks.
+		c := br.getColumnByName(fields[0])
+		if c.isTime {
+			// Count unique br.timestamps
+			timestamps := br.timestamps
+			keyBuf := sup.keyBuf[:0]
+			for i, timestamp := range timestamps {
+				if i > 0 && timestamps[i-1] == timestamps[i] {
+					// This timestamp has been already counted.
+					continue
+				}
+				keyBuf = append(keyBuf[:0], 1)
+				keyBuf = encoding.MarshalInt64(keyBuf, timestamp)
+				if _, ok := m[string(keyBuf)]; !ok {
+					m[string(keyBuf)] = struct{}{}
+					stateSizeIncrease += len(keyBuf) + int(unsafe.Sizeof(""))
+				}
+			}
+			sup.keyBuf = keyBuf
+			return stateSizeIncrease
+		}
+		if c.isConst {
+			// count unique const values
+			v := c.encodedValues[0]
+			if v == "" {
+				// Do not count empty values
+				return stateSizeIncrease
+			}
+			keyBuf := sup.keyBuf[:0]
+			keyBuf = append(keyBuf[:0], 0, byte(valueTypeString))
+			keyBuf = append(keyBuf, v...)
+			if _, ok := m[string(keyBuf)]; !ok {
+				m[string(keyBuf)] = struct{}{}
+				stateSizeIncrease += len(keyBuf) + int(unsafe.Sizeof(""))
+			}
+			sup.keyBuf = keyBuf
+			return stateSizeIncrease
+		}
+		if c.valueType == valueTypeDict {
+			// count unique non-zero c.dictValues
+			keyBuf := sup.keyBuf[:0]
+			for i, v := range c.dictValues {
 				if v == "" {
 					// Do not count empty values
 					continue
 				}
-				if i > 0 && values[i-1] == v {
-					continue
-				}
-				if _, ok := m[v]; !ok {
-					vCopy := strings.Clone(v)
-					m[vCopy] = struct{}{}
-					stateSizeIncrease += len(vCopy) + int(unsafe.Sizeof(vCopy))
+				keyBuf = append(keyBuf[:0], 0, byte(valueTypeDict))
+				keyBuf = append(keyBuf, byte(i))
+				if _, ok := m[string(keyBuf)]; !ok {
+					m[string(keyBuf)] = struct{}{}
+					stateSizeIncrease += len(keyBuf) + int(unsafe.Sizeof(""))
 				}
 			}
+			sup.keyBuf = keyBuf
+			return stateSizeIncrease
 		}
+
+		// Count unique values across encodedValues
+		encodedValues := c.getEncodedValues(br)
+		isStringValueType := c.valueType == valueTypeString
+		keyBuf := sup.keyBuf[:0]
+		for i, v := range encodedValues {
+			if isStringValueType && v == "" {
+				// Do not count empty values
+				continue
+			}
+			if i > 0 && encodedValues[i-1] == v {
+				// This value has been already counted.
+				continue
+			}
+			keyBuf = append(keyBuf[:0], 0, byte(c.valueType))
+			keyBuf = append(keyBuf, v...)
+			if _, ok := m[string(keyBuf)]; !ok {
+				m[string(keyBuf)] = struct{}{}
+				stateSizeIncrease += len(keyBuf) + int(unsafe.Sizeof(""))
+			}
+		}
+		keyBuf = sup.keyBuf
 		return stateSizeIncrease
 	}
 
 	// Slow path for multiple columns.
 
 	// Pre-calculate column values for byFields in order to speed up building group key in the loop below.
-	sup.columnValues = appendBlockColumnValues(sup.columnValues[:0], columns, fields, len(timestamps))
+	sup.columnValues = br.appendColumnValues(sup.columnValues[:0], fields)
 	columnValues := sup.columnValues
 
-	keyBuf := sup.keyBuf
-	for i := range timestamps {
+	keyBuf := sup.keyBuf[:0]
+	for i := range br.timestamps {
 		seenKey := true
 		for _, values := range columnValues {
 			if i == 0 || values[i-1] != values[i] {
 				seenKey = false
+				break
 			}
 		}
 		if seenKey {
@@ -149,7 +214,7 @@ func (sup *statsUniqProcessor) updateStatsForAllRows(timestamps []int64, columns
 	return stateSizeIncrease
 }
 
-func (sup *statsUniqProcessor) updateStatsForRow(timestamps []int64, columns []BlockColumn, rowIdx int) int {
+func (sup *statsUniqProcessor) updateStatsForRow(br *blockResult, rowIdx int) int {
 	fields := sup.su.fields
 	m := sup.m
 
@@ -158,13 +223,13 @@ func (sup *statsUniqProcessor) updateStatsForRow(timestamps []int64, columns []B
 		// Count unique rows
 		allEmptyValues := true
 		keyBuf := sup.keyBuf[:0]
-		for _, c := range columns {
-			v := c.Values[rowIdx]
+		for _, c := range br.getColumns() {
+			v := c.getValueAtRow(br, rowIdx)
 			if v != "" {
 				allEmptyValues = false
 			}
 			// Put column name into key, since every block can contain different set of columns for '*' selector.
-			keyBuf = encoding.MarshalBytes(keyBuf, bytesutil.ToUnsafeBytes(c.Name))
+			keyBuf = encoding.MarshalBytes(keyBuf, bytesutil.ToUnsafeBytes(c.name))
 			keyBuf = encoding.MarshalBytes(keyBuf, bytesutil.ToUnsafeBytes(v))
 		}
 		sup.keyBuf = keyBuf
@@ -180,19 +245,73 @@ func (sup *statsUniqProcessor) updateStatsForRow(timestamps []int64, columns []B
 		return stateSizeIncrease
 	}
 	if len(fields) == 1 {
-		// Fast path for a single column
-		if idx := getBlockColumnIndex(columns, fields[0]); idx >= 0 {
-			v := columns[idx].Values[rowIdx]
+		// Fast path for a single column.
+		// The unique key is formed as "<is_time> <value_type>? <encodedValue>",
+		// where <value_type> is skipped if <is_time> == 1.
+		// This guarantees that keys do not clash for different column types acorss blocks.
+		c := br.getColumnByName(fields[0])
+		if c.isTime {
+			// Count unique br.timestamps
+			keyBuf := sup.keyBuf[:0]
+			keyBuf = append(keyBuf[:0], 1)
+			keyBuf = encoding.MarshalInt64(keyBuf, br.timestamps[rowIdx])
+			if _, ok := m[string(keyBuf)]; !ok {
+				m[string(keyBuf)] = struct{}{}
+				stateSizeIncrease += len(keyBuf) + int(unsafe.Sizeof(""))
+			}
+			sup.keyBuf = keyBuf
+			return stateSizeIncrease
+		}
+		if c.isConst {
+			// count unique const values
+			v := c.encodedValues[0]
 			if v == "" {
 				// Do not count empty values
 				return stateSizeIncrease
 			}
-			if _, ok := m[v]; !ok {
-				vCopy := strings.Clone(v)
-				m[vCopy] = struct{}{}
-				stateSizeIncrease += len(vCopy) + int(unsafe.Sizeof(vCopy))
+			keyBuf := sup.keyBuf[:0]
+			keyBuf = append(keyBuf[:0], 0, byte(valueTypeString))
+			keyBuf = append(keyBuf, v...)
+			if _, ok := m[string(keyBuf)]; !ok {
+				m[string(keyBuf)] = struct{}{}
+				stateSizeIncrease += len(keyBuf) + int(unsafe.Sizeof(""))
 			}
+			sup.keyBuf = keyBuf
+			return stateSizeIncrease
 		}
+		if c.valueType == valueTypeDict {
+			// count unique non-zero c.dictValues
+			dictIdx := c.encodedValues[rowIdx][0]
+			if c.dictValues[dictIdx] == "" {
+				// Do not count empty values
+				return stateSizeIncrease
+			}
+			keyBuf := sup.keyBuf[:0]
+			keyBuf = append(keyBuf[:0], 0, byte(valueTypeDict))
+			keyBuf = append(keyBuf, dictIdx)
+			if _, ok := m[string(keyBuf)]; !ok {
+				m[string(keyBuf)] = struct{}{}
+				stateSizeIncrease += len(keyBuf) + int(unsafe.Sizeof(""))
+			}
+			sup.keyBuf = keyBuf
+			return stateSizeIncrease
+		}
+
+		// Count unique values across encodedValues
+		encodedValues := c.getEncodedValues(br)
+		v := encodedValues[rowIdx]
+		if c.valueType == valueTypeString && v == "" {
+			// Do not count empty values
+			return stateSizeIncrease
+		}
+		keyBuf := sup.keyBuf[:0]
+		keyBuf = append(keyBuf[:0], 0, byte(c.valueType))
+		keyBuf = append(keyBuf, v...)
+		if _, ok := m[string(keyBuf)]; !ok {
+			m[string(keyBuf)] = struct{}{}
+			stateSizeIncrease += len(keyBuf) + int(unsafe.Sizeof(""))
+		}
+		keyBuf = sup.keyBuf
 		return stateSizeIncrease
 	}
 
@@ -200,10 +319,8 @@ func (sup *statsUniqProcessor) updateStatsForRow(timestamps []int64, columns []B
 	allEmptyValues := true
 	keyBuf := sup.keyBuf[:0]
 	for _, f := range fields {
-		v := ""
-		if idx := getBlockColumnIndex(columns, f); idx >= 0 {
-			v = columns[idx].Values[rowIdx]
-		}
+		c := br.getColumnByName(f)
+		v := c.getValueAtRow(br, rowIdx)
 		if v != "" {
 			allEmptyValues = false
 		}
diff --git a/lib/logstorage/storage_search.go b/lib/logstorage/storage_search.go
index d70dcfc32..1cb3ebb41 100644
--- a/lib/logstorage/storage_search.go
+++ b/lib/logstorage/storage_search.go
@@ -63,7 +63,24 @@ func (s *Storage) RunQuery(ctx context.Context, tenantIDs []TenantID, q *Query,
 
 	workersCount := cgroup.AvailableCPUs()
 
-	pp := newDefaultPipeProcessor(writeBlock)
+	pp := newDefaultPipeProcessor(func(workerID uint, br *blockResult) {
+		brs := getBlockRows()
+		csDst := brs.cs
+
+		csSrc := br.getColumns()
+		for _, c := range csSrc {
+			values := c.getValues(br)
+			csDst = append(csDst, BlockColumn{
+				Name:   c.name,
+				Values: values,
+			})
+		}
+		writeBlock(workerID, br.timestamps, csDst)
+
+		brs.cs = csDst
+		putBlockRows(brs)
+	})
+
 	ppMain := pp
 	stopCh := ctx.Done()
 	cancels := make([]func(), len(q.pipes))
@@ -79,21 +96,7 @@ func (s *Storage) RunQuery(ctx context.Context, tenantIDs []TenantID, q *Query,
 		pps[i] = pp
 	}
 
-	s.search(workersCount, so, stopCh, func(workerID uint, br *blockResult) {
-		brs := getBlockRows()
-		cs := brs.cs
-
-		for i, columnName := range br.columnNames {
-			cs = append(cs, BlockColumn{
-				Name:   columnName,
-				Values: br.getColumnValues(i),
-			})
-		}
-		pp.writeBlock(workerID, br.timestamps, cs)
-
-		brs.cs = cs
-		putBlockRows(brs)
-	})
+	s.search(workersCount, so, stopCh, pp.writeBlock)
 
 	var errFlush error
 	for i, pp := range pps {
@@ -150,18 +153,6 @@ func (c *BlockColumn) reset() {
 	c.Values = nil
 }
 
-func areSameBlockColumns(columns []BlockColumn, columnNames []string) bool {
-	if len(columnNames) != len(columns) {
-		return false
-	}
-	for i, name := range columnNames {
-		if columns[i].Name != name {
-			return false
-		}
-	}
-	return true
-}
-
 func getBlockColumnIndex(columns []BlockColumn, columnName string) int {
 	for i, c := range columns {
 		if c.Name == columnName {
@@ -237,7 +228,7 @@ func (s *Storage) search(workersCount int, so *genericSearchOptions, stopCh <-ch
 					}
 
 					bs.search(bsw)
-					if bs.br.RowsCount() > 0 {
+					if len(bs.br.timestamps) > 0 {
 						processBlockResult(workerID, &bs.br)
 					}
 				}
diff --git a/lib/logstorage/storage_search_test.go b/lib/logstorage/storage_search_test.go
index 349b3b2f6..5c1c00bbf 100644
--- a/lib/logstorage/storage_search_test.go
+++ b/lib/logstorage/storage_search_test.go
@@ -466,7 +466,7 @@ func TestStorageSearch(t *testing.T) {
 				if !br.streamID.tenantID.equal(&tenantID) {
 					panic(fmt.Errorf("unexpected tenantID; got %s; want %s", &br.streamID.tenantID, &tenantID))
 				}
-				rowsCountTotal.Add(uint32(br.RowsCount()))
+				rowsCountTotal.Add(uint32(len(br.timestamps)))
 			}
 			s.search(workersCount, so, nil, processBlock)
 
@@ -487,7 +487,7 @@ func TestStorageSearch(t *testing.T) {
 		}
 		var rowsCountTotal atomic.Uint32
 		processBlock := func(_ uint, br *blockResult) {
-			rowsCountTotal.Add(uint32(br.RowsCount()))
+			rowsCountTotal.Add(uint32(len(br.timestamps)))
 		}
 		s.search(workersCount, so, nil, processBlock)
 
@@ -531,7 +531,7 @@ func TestStorageSearch(t *testing.T) {
 				if !br.streamID.tenantID.equal(&tenantID) {
 					panic(fmt.Errorf("unexpected tenantID; got %s; want %s", &br.streamID.tenantID, &tenantID))
 				}
-				rowsCountTotal.Add(uint32(br.RowsCount()))
+				rowsCountTotal.Add(uint32(len(br.timestamps)))
 			}
 			s.search(workersCount, so, nil, processBlock)
 
@@ -560,7 +560,7 @@ func TestStorageSearch(t *testing.T) {
 			if !br.streamID.tenantID.equal(&tenantID) {
 				panic(fmt.Errorf("unexpected tenantID; got %s; want %s", &br.streamID.tenantID, &tenantID))
 			}
-			rowsCountTotal.Add(uint32(br.RowsCount()))
+			rowsCountTotal.Add(uint32(len(br.timestamps)))
 		}
 		s.search(workersCount, so, nil, processBlock)
 
@@ -597,7 +597,7 @@ func TestStorageSearch(t *testing.T) {
 			if !br.streamID.tenantID.equal(&tenantID) {
 				panic(fmt.Errorf("unexpected tenantID; got %s; want %s", &br.streamID.tenantID, &tenantID))
 			}
-			rowsCountTotal.Add(uint32(br.RowsCount()))
+			rowsCountTotal.Add(uint32(len(br.timestamps)))
 		}
 		s.search(workersCount, so, nil, processBlock)
 
@@ -622,7 +622,7 @@ func TestStorageSearch(t *testing.T) {
 		}
 		var rowsCountTotal atomic.Uint32
 		processBlock := func(_ uint, br *blockResult) {
-			rowsCountTotal.Add(uint32(br.RowsCount()))
+			rowsCountTotal.Add(uint32(len(br.timestamps)))
 		}
 		s.search(workersCount, so, nil, processBlock)