feat(backend):关联视图表、字段重复关联校验

backend/src/main/java/io/dataease/service/dataset/DataSetTableUnionService.java

@@ -88,6 +88,7 @@ public class DataSetTableUnionService {
         criteria.andTargetTableFieldIdEqualTo(datasetTableUnion.getTargetTableFieldId());
         List<DatasetTableUnion> sourceResult = datasetTableUnionMapper.selectByExample(datasetTableUnionExample);
         datasetTableUnionExample.clear();
+        criteria = datasetTableUnionExample.createCriteria();
         if (StringUtils.isNotEmpty(datasetTableUnion.getId())) {
             criteria.andIdNotEqualTo(datasetTableUnion.getId());
         }

frontend/src/views/dataset/data/UnionView.vue

@@ -230,6 +230,7 @@ export default {
         targetTableFieldId: '',
         targetUnionRelation: ''
       }
+      this.targetTable = {}
     },
 
     edit(item) {