diff --git a/cdc/model/sink.go b/cdc/model/sink.go
index 019728f40fd..3632072bfbd 100644
--- a/cdc/model/sink.go
+++ b/cdc/model/sink.go
@@ -1347,3 +1347,34 @@ func (x ColumnDataX) GetDefaultValue() interface{} {
 func (x ColumnDataX) GetColumnInfo() *model.ColumnInfo {
 	return x.info
 }
+
+// Column2ColumnDataForTest is for tests.
+func Column2ColumnDataForTest(columns []*Column) ([]*ColumnData, *TableInfo) {
+	info := &TableInfo{
+		TableInfo: &model.TableInfo{
+			Columns: make([]*model.ColumnInfo, len(columns)),
+		},
+		ColumnsFlag:   make(map[int64]*ColumnFlagType, len(columns)),
+		columnsOffset: make(map[int64]int),
+	}
+	colDatas := make([]*ColumnData, 0, len(columns))
+
+	for i, column := range columns {
+		var columnID int64 = int64(i)
+		info.columnsOffset[columnID] = i
+
+		info.Columns[i] = &model.ColumnInfo{}
+		info.Columns[i].Name.O = column.Name
+		info.Columns[i].SetType(column.Type)
+		info.Columns[i].SetCharset(column.Charset)
+		info.Columns[i].SetCollate(column.Collation)
+		info.Columns[i].DefaultValue = column.Default
+
+		info.ColumnsFlag[columnID] = new(ColumnFlagType)
+		*info.ColumnsFlag[columnID] = column.Flag
+
+		colDatas = append(colDatas, &ColumnData{ColumnID: columnID, Value: column.Value})
+	}
+
+	return colDatas, info
+}
diff --git a/cdc/sink/dmlsink/txn/event_test.go b/cdc/sink/dmlsink/txn/event_test.go
index bdbb5cd7db9..31e2e05bf16 100644
--- a/cdc/sink/dmlsink/txn/event_test.go
+++ b/cdc/sink/dmlsink/txn/event_test.go
@@ -25,24 +25,24 @@ import (
 func TestGenKeyListCaseInSensitive(t *testing.T) {
 	t.Parallel()
 
-	columns := []*model.Column{
+	columns, tb := model.Column2ColumnDataForTest([]*model.Column{
 		{
 			Value:     "XyZ",
 			Type:      mysql.TypeVarchar,
 			Collation: "utf8_unicode_ci",
 		},
-	}
+	})
 
-	first := genKeyList(columns, 0, []int{0}, 1)
+	first := genKeyList(columns, tb, 0, []int{0}, 1)
 
-	columns = []*model.Column{
+	columns, tb = model.Column2ColumnDataForTest([]*model.Column{
 		{
 			Value:     "xYZ",
 			Type:      mysql.TypeVarchar,
 			Collation: "utf8_unicode_ci",
 		},
-	}
-	second := genKeyList(columns, 0, []int{0}, 1)
+	})
+	second := genKeyList(columns, tb, 0, []int{0}, 1)
 
 	require.Equal(t, first, second)
 }
diff --git a/cdc/sink/dmlsink/txn/mysql/dml.go b/cdc/sink/dmlsink/txn/mysql/dml.go
index abbe1067874..92802c9ad41 100644
--- a/cdc/sink/dmlsink/txn/mysql/dml.go
+++ b/cdc/sink/dmlsink/txn/mysql/dml.go
@@ -157,29 +157,25 @@ func prepareDelete(quoteTable string, cols []*model.ColumnData, tb *model.TableI
 // whereSlice builds a parametric WHERE clause as following
 // sql: `WHERE {} = ? AND {} > ?`
 func whereSlice(cols []*model.ColumnData, tb *model.TableInfo, forceReplicate bool) (colNames []string, args []interface{}) {
-	// If no explicit row id but force replicate, use all key-values in where condition.
+	// Try to use unique key values when available
+	for _, col := range cols {
+		colx := model.GetColumnDataX(col, tb)
+		if colx.ColumnData == nil || !colx.GetFlag().IsHandleKey() {
+			continue
+		}
+		colNames = append(colNames, colx.GetName())
+		args = appendQueryArgs(args, colx)
+	}
+	// if no explicit row id but force replicate, use all key-values in where condition
 	if len(colNames) == 0 && forceReplicate {
 		colNames = make([]string, 0, len(cols))
 		args = make([]interface{}, 0, len(cols))
 		for _, col := range cols {
 			colx := model.GetColumnDataX(col, tb)
-			if colx.ColumnData == nil {
-				continue
-			}
-			colNames = append(colNames, colx.GetName())
-			args = appendQueryArgs(args, colx)
-		}
-	} else { // Try to use unique key values when available.
-		for _, col := range cols {
-			colx := model.GetColumnDataX(col, tb)
-			if colx.ColumnData == nil || !colx.GetFlag().IsHandleKey() {
-				continue
-			}
 			colNames = append(colNames, colx.GetName())
 			args = appendQueryArgs(args, colx)
 		}
 	}
-
 	return
 }
 
diff --git a/cdc/sink/dmlsink/txn/mysql/dml_test.go b/cdc/sink/dmlsink/txn/mysql/dml_test.go
index dab7c4b104f..20f22d63c2b 100644
--- a/cdc/sink/dmlsink/txn/mysql/dml_test.go
+++ b/cdc/sink/dmlsink/txn/mysql/dml_test.go
@@ -250,7 +250,9 @@ func TestPrepareUpdate(t *testing.T) {
 		},
 	}
 	for _, tc := range testCases {
-		query, args := prepareUpdate(tc.quoteTable, tc.preCols, tc.cols, false)
+		preDatas, info := model.Column2ColumnDataForTest(tc.preCols)
+		datas, _ := model.Column2ColumnDataForTest(tc.cols)
+		query, args := prepareUpdate(tc.quoteTable, preDatas, datas, info, false)
 		require.Equal(t, tc.expectedSQL, query)
 		require.Equal(t, tc.expectedArgs, args)
 	}
@@ -392,7 +394,8 @@ func TestPrepareDelete(t *testing.T) {
 		},
 	}
 	for _, tc := range testCases {
-		query, args := prepareDelete(tc.quoteTable, tc.preCols, false)
+		preDatas, info := model.Column2ColumnDataForTest(tc.preCols)
+		query, args := prepareDelete(tc.quoteTable, preDatas, info, false)
 		require.Equal(t, tc.expectedSQL, query)
 		require.Equal(t, tc.expectedArgs, args)
 	}
@@ -601,9 +604,10 @@ func TestWhereSlice(t *testing.T) {
 			expectedArgs:     []interface{}{1, "你好", 100},
 		},
 	}
-	for _, tc := range testCases {
-		colNames, args := whereSlice(tc.cols, tc.forceReplicate)
-		require.Equal(t, tc.expectedColNames, colNames)
+	for i, tc := range testCases {
+		datas, info := model.Column2ColumnDataForTest(tc.cols)
+		colNames, args := whereSlice(datas, info, tc.forceReplicate)
+		require.Equal(t, tc.expectedColNames, colNames, "case %d fails", i)
 		require.Equal(t, tc.expectedArgs, args)
 	}
 }
@@ -713,7 +717,8 @@ func TestMapReplace(t *testing.T) {
 	for _, tc := range testCases {
 		// multiple times to verify the stability of column sequence in query string
 		for i := 0; i < 10; i++ {
-			query, args := prepareReplace(tc.quoteTable, tc.cols, false, false)
+			datas, info := model.Column2ColumnDataForTest(tc.cols)
+			query, args := prepareReplace(tc.quoteTable, datas, info, false, false)
 			require.Equal(t, tc.expectedQuery, query)
 			require.Equal(t, tc.expectedArgs, args)
 		}