docs: private void insert(ESSyncConfig config, Dml dml) {
          List<Map<String, Object>> dataList = dml.getData();
          if (dataList == null || dataList.isEmpty()) {
              return;
          }
          SchemaItem schemaItem = config.getEsMapping().getSchemaItem();
          for (Map<String, Object> data : dataList) {
              if (data == null || data.isEmpty()) {
                  continue;
              }
  
              if (schemaItem.getAliasTableItems().size() == 1 && schemaItem.isAllFieldsSimple()) {
                  // ------单表 & 所有字段都为简单字段------
                  singleTableSimpleFiledInsert(config, dml, data);
              } else {
                  // ------是主表 查询sql来插入------
                  if (schemaItem.getMainTable().getTableName().equalsIgnoreCase(dml.getTable())) {
                      mainTableInsert(config, dml, data);
                  }
  
                  // 从表的操作
                  for (TableItem tableItem : schemaItem.getAliasTableItems().values()) {
                      if (tableItem.isMain()) {
                          continue;
                      }
                      if (!tableItem.getTableName().equals(dml.getTable())) {
                          continue;
                      }
                      // 关联条件出现在主表查询条件是否为简单字段
                      boolean allFieldsSimple = true;
                      for (FieldItem fieldItem : tableItem.getRelationSelectFieldItems()) {
                          if (fieldItem.isMethod() || fieldItem.isBinaryOp()) {
                              allFieldsSimple = false;
                              break;
                          }
                      }
                      // 所有查询字段均为简单字段
                      if (allFieldsSimple) {
                          // 不是子查询
                          if (!tableItem.isSubQuery()) {
                              // ------关联表简单字段插入------
                              Map<String, Object> esFieldData = new LinkedHashMap<>();
                              for (FieldItem fieldItem : tableItem.getRelationSelectFieldItems()) {
                                  Object value = esTemplate.getValFromData(config.getEsMapping(),
                                      data,
                                      fieldItem.getFieldName(),
                                      fieldItem.getColumn().getColumnName());
                                  esFieldData.put(Util.cleanColumn(fieldItem.getFieldName()), value);
                              }
  
                              joinTableSimpleFieldOperation(config, dml, data, tableItem, esFieldData);
                          } else {
                              // ------关联子表简单字段插入------
                              subTableSimpleFieldOperation(config, dml, data, null, tableItem);
                          }
                      } else {
                          // ------关联子表复杂字段插入 执行全sql更新es------
                          wholeSqlOperation(config, dml, data, null, tableItem);
                      }
                  }
              }
          }
      }