fix: Fix import failed due to 0 row num (#39903)

pr: #39886
issue: #39885

Signed-off-by: zhenshan.cao <zhenshan.cao@zilliz.com>

Author: czs007

internal/datanode/importv2/task_import.go

@@ -185,7 +185,12 @@ func (t *ImportTask) importFile(reader importutilv2.Reader) error {
 			}
 			return err
 		}
-		err = AppendSystemFieldsData(t, data)
+		rowNum := GetInsertDataRowCount(data, t.GetSchema())
+		if rowNum == 0 {
+			log.Info("0 row was imported, the data may have been deleted", WrapLogFields(t)...)
+			continue
+		}
+		err = AppendSystemFieldsData(t, data, rowNum)
 		if err != nil {
 			return err
 		}

internal/datanode/importv2/util.go

@@ -164,13 +164,12 @@ func CheckRowsEqual(schema *schemapb.CollectionSchema, data *storage.InsertData)
 	return nil
 }
 
-func AppendSystemFieldsData(task *ImportTask, data *storage.InsertData) error {
+func AppendSystemFieldsData(task *ImportTask, data *storage.InsertData, rowNum int) error {
 	idRange := task.req.GetIDRange()
 	pkField, err := typeutil.GetPrimaryFieldSchema(task.GetSchema())
 	if err != nil {
 		return err
 	}
-	rowNum := GetInsertDataRowCount(data, task.GetSchema())
 	ids := make([]int64, rowNum)
 	for i := 0; i < rowNum; i++ {
 		ids[i] = idRange.GetBegin() + int64(i)

internal/datanode/importv2/util_test.go

@@ -73,7 +73,8 @@ func Test_AppendSystemFieldsData(t *testing.T) {
 	assert.Equal(t, 0, insertData.Data[pkField.GetFieldID()].RowNum())
 	assert.Nil(t, insertData.Data[common.RowIDField])
 	assert.Nil(t, insertData.Data[common.TimeStampField])
-	err = AppendSystemFieldsData(task, insertData)
+	rowNum := GetInsertDataRowCount(insertData, task.GetSchema())
+	err = AppendSystemFieldsData(task, insertData, rowNum)
 	assert.NoError(t, err)
 	assert.Equal(t, count, insertData.Data[pkField.GetFieldID()].RowNum())
 	assert.Equal(t, count, insertData.Data[common.RowIDField].RowNum())
@@ -86,7 +87,8 @@ func Test_AppendSystemFieldsData(t *testing.T) {
 	assert.Equal(t, 0, insertData.Data[pkField.GetFieldID()].RowNum())
 	assert.Nil(t, insertData.Data[common.RowIDField])
 	assert.Nil(t, insertData.Data[common.TimeStampField])
-	err = AppendSystemFieldsData(task, insertData)
+	rowNum = GetInsertDataRowCount(insertData, task.GetSchema())
+	err = AppendSystemFieldsData(task, insertData, rowNum)
 	assert.NoError(t, err)
 	assert.Equal(t, count, insertData.Data[pkField.GetFieldID()].RowNum())
 	assert.Equal(t, count, insertData.Data[common.RowIDField].RowNum())