remove debug log and add comments

executor/table_reader.go

@@ -17,7 +17,6 @@ package executor
 import (
 	"bytes"
 	"context"
-	"fmt"
 	"time"
 
 	"github.com/opentracing/opentracing-go"
@@ -41,7 +40,6 @@ import (
 	"github.com/pingcap/tidb/util/ranger"
 	"github.com/pingcap/tidb/util/stringutil"
 	"github.com/pingcap/tipb/go-tipb"
-	"go.uber.org/zap"
 	"golang.org/x/exp/slices"
 )
 
@@ -188,9 +186,6 @@ func (e *TableReaderExecutor) Open(ctx context.Context) error {
 	}
 	firstPartRanges, secondPartRanges := distsql.SplitRangesAcrossInt64Boundary(e.ranges, e.keepOrder, e.desc, e.table.Meta() != nil && e.table.Meta().IsCommonHandle)
 
-	if !e.ctx.GetSessionVars().InRestrictedSQL {
-		logutil.BgLogger().Warn("build table ranges", zap.String("first part", fmt.Sprintf("%v", firstPartRanges)), zap.String("second part", fmt.Sprintf("%v", secondPartRanges)))
-	}
 	// Treat temporary table as dummy table, avoid sending distsql request to TiKV.
 	// Calculate the kv ranges here, UnionScan rely on this kv ranges.
 	// cached table and temporary table are similar

planner/core/task.go

@@ -1104,7 +1104,7 @@ func (p *PhysicalTopN) pushTopNDownToDynamicPartition(copTsk *copTask) (task, bo
 			}
 		}
 		tblScan.Desc = isDesc
-		// SplitRangesAcrossInt64Boundary needs the KeepOrder flag. See that func for more details.
+		// SplitRangesAcrossInt64Boundary needs the KeepOrder flag. See that func and the struct tableResultHandler for more details.
 		tblScan.KeepOrder = true
 		childProfile := copTsk.plan().statsInfo()
 		newCount := p.Offset + p.Count