EF LEFT JON 关联查找

var query = (from a in context.OQC_INSPECTION_SAMPLE.Where(expression).Where(a => context.OQC_INSPECTION_SAMPLE_ITEM.Where(b => b.SAMPLE_INSPECTION_ID == a.ID).Where(expression2).Any())
                                     join b in context.OQC_INSP_SAMPLE_RPT.Where(expression1)
                                         on a.ID equals b.REF_SAMPLE_ID into gc

                                     where a.STATE == StateConverter.Active && a.ORG_ID == standard.ORG_ID
                                     from gci in gc.DefaultIfEmpty()
                                     select new
                                     {

                                         Str_Array = a.ID + "#" + a.PROD_ID + "#" + a.INSPECTION_NO + "#" + a.WORK_ORDER_ID + "#" + a.PROD_MODEL_ID + "#" + a.TEAM_GROUP,
                                         a.APPROVER,
                                         a.BARCODE,
                                         a.BARCODE_COMPLETION_TIME,
                                         a.BATCH_NO,
                                         a.CLIENT_NAME,
                                         a.CLIENT_ORDER_ID,
                                         a.COMPLETE_COUNT,
                                         a.DATETIME_CREATED,
                                         a.DATETIME_MODIFIED,
                                         a.DATETIME_REPORT_GENERATED,
                                         a.ELT_RESULT,
                                         a.FAIL_COUNT,
                                         a.FAIL_DESC,
                                         a.FEATURES_LEVEL,
                                         a.GROSS_WEIGHT,
                                         a.ID,
                                         a.INSPECTION_COUNT,
                                         a.INSPECTION_LEVEL,
                                         a.INSPECTION_NO,
                                         a.INSPECTION_RESULT,
                                         a.INSPECTION_TIME,
                                         a.INSPECTOR,
                                         a.IS_CHANGESTD1,
                                         a.IS_INSPECTOR,
                                         a.MANTISSA,
                                         a.NET_WEIGHT,
                                         a.ORG_ID,
                                         a.PROD_DESC,
                                         a.PROD_MODEL_ID,
                                         a.PROD_ID,
                                         a.PRODUCTION_END_TIME,
                                         a.PRODUCTION_LINE,
                                         a.PRODUCTION_START_TIME,
                                         a.RECEIPTS_TIME,
                                         a.RECTIFY,
                                         a.RECTIFY_OPINION,
                                         a.REMADE_INSPECTION_NO,
                                         a.REMADE_REPORT_NO,
                                         a.REMADE_RESULT,
                                         a.REMARK,
                                         a.SAMPLE_COUNT,
                                         a.SAMPLING_PERCENT,
                                         a.SAMPLING_STANDARD,
                                         a.SN,
                                         a.SOLD_TO,
                                         a.SOLD_TO_DISPLAY,
                                         a.STANDARD_NAME,
                                         a.STATE,
                                         a.STATUS,
                                         a.STOP_PRODUCTION,
                                         a.STRICT_LEVEL,
                                         a.TEAM_GROUP,
                                         a.USER_CREATED,
                                         a.USER_CREATED_NAME,
                                         a.USER_MODIFIED,
                                         a.USER_MODIFIED_NAME,
                                         a.WORK_ORDER_ID,
                                         a.WORK_ORDER_QTY,
                                         a.WORKSHOP,
                                         a.PRODUCT_INFO,
                                         rpt_id =gci==null?"": gci.ID,
                                         joinstate = gci==null?"N":(gci.JOINSTATE == null ? "N" : gci.JOINSTATE),
                                     });
                        totalRecords = query.Count();
                        return query.OrderByDescending(a => new { a.DATETIME_CREATED, a.DATETIME_MODIFIED })
                                    .Skip(viewQueryModel.start).Take(viewQueryModel.length).ToList();
                    }