fix: writing to disk ,some records will be dropped when the point on… (openGemini#609)

Signed-off-by: PennyYoon <[email protected]>

Author: Chenxulin97

engine/immutable/column_builder.go

@@ -487,7 +487,7 @@ func DecodeColumnHeader(col *record.ColVal, data []byte, colType uint8) ([]byte,
 }
 
 func CanEncodeOneRowMode(col *record.ColVal) bool {
-	return col.Len == 1 && len(col.Val) < 16
+	return col.Len == 1 && len(col.Val) < 16 && len(col.Val) > 0
 }
 
 func rewriteType(col *record.ColVal, typ uint8) uint8 {

engine/immutable/merge_tool_test.go

@@ -922,6 +922,11 @@ func TestMergeTool_OneRowMode(t *testing.T) {
 
 	rg.setBegin(begin).incrBegin(0)
 	mh.addRecord(100, rg.generate(schemas, 1001))
+	rec := rg.generate(schemas, 1)
+	col := rec.Column(3)
+	col.Init()
+	col.AppendStrings("")
+	mh.addRecord(101, rec)
 	require.NoError(t, mh.saveToOrder())
 
 	rg.setBegin(begin - 1).incrBegin(5)

engine/immutable/reader_test.go

@@ -632,12 +632,7 @@ func TestEncodeOneRowMode(t *testing.T) {
 	codec.dataCol.Init()
 	codec.dataCol.AppendIntegerNull()
 	codec.encode(t)
-	codec.assertEncodeDataSize(t, 1)
-
-	DecodeColumnOfOneValue(codec.buf[1:], other, influx.Field_Type_Int)
-	require.Equal(t, 1, other.Len)
-	require.Equal(t, 1, other.NilCount)
-	require.Equal(t, 0, len(other.Val))
+	codec.assertEncodeDataSize(t, 5)
 
 	var s = ""
 	for i := 0; i < 50; i++ {