连接两个具有不同键名的表

Posted 2023-03-25

【中文标题】连接两个具有不同键名的表

【英文标题】：Join two tables with different key name

【发布时间】：2018-12-03 14:13:07

【问题描述】：

尝试实现以下场景，

使用相同的键连接两个表（A、B） 过滤表（c） 加入第 1 步的结果和第 2 步的结果。这里它有不同的键名但相同的值（例如：第一个表列名是“id”第二个表列名是“Fid”但两个值相同）。

使用 Cloud Dataflow 执行代码时出现以下错误，

严重：2018-12-03T13:52:47.634Z: java.lang.IllegalStateException: 需要唯一键，但发现键 127348#null 值为 HEADER_ID=18219955, ORDER_TYPE_ID=2124, ORDER_NUMBER=729637, ORDERED_DATE=10 /29/2018 下午 4:01:25，TRANSACTIONAL_CURR_CODE=USD，CUST_PO_NUMBER=942634，SOLD_TO_ORG_ID=127348，SHIP_FROM_ORG_ID=934，PRICE_LIST_ID=7035，CREATION_DATE=2018-10-29 16:10:41 UTC，LAST_UPDATE_DATE -29 16:10:13 UTC，FLOW_STATUS_CODE=BOOKED 和 HEADER_ID=18219945，ORDER_TYPE_ID=2124，ORDER_NUMBER=729636，ORDERED_DATE=10/29/2018 3:56:05 PM，TRANSACTIONAL_CURR_CODE=USD，CUST_PO_NUMBER=941674，SOLDTO_ORGID =127348, SHIP_FROM_ORG_ID=934, PRICE_LIST_ID=7035, CREATION_DATE=2018-10-29 15:10:20 UTC, LAST_UPDATE_DATE=2018-10-29 16:10:34 UTC, FLOW_STATUS_CODE=BOOKED 在窗口 org.apache.beam .sdk.transforms.windowing.GlobalWindow@6c5cc8ee。 在 org.apache.beam.runners.dataflow.BatchViewOverrides$BatchViewAsMultimap$ToIsmRecordForMapLikeDoFn.processElement(BatchViewOverrides.java:442)

这是我尝试过的全部代码：

WithKeys<String, TableRow> headerKey = WithKeys.of( (TableRow row) -> String.format("%s",row.get("PARTY_ID"))).withKeyType(TypeDescriptors.strings());

            PCollection<KV<String,TableRow>> mainInput = p.apply("ReadCustomerAccount",BigQueryIO.readTableRows().from(options.getCustAccount())).apply("WithKeys", headerKey);
            PCollection<KV<String,TableRow>> sideInput = p.apply("ReadCustomerParty",BigQueryIO.readTableRows().from(options.getPartyTable())).apply("WithKeys", headerKey);


            PCollection<TableRow> result  = CommonFunctions.innerJoinBQTbls("InnerJoin",mainInput,sideInput);

            @SuppressWarnings("serial")
            PCollection<TableRow> finalResultCollection =  result.apply("Process", ParDo.of(new DoFn<TableRow, TableRow>() 
            
                  @ProcessElement
                  public void processElement(ProcessContext c) 
                  
                      TableRow keyString = c.element();

                      TableRow mainList = (TableRow) keyString.get("main");
                      TableRow sideList = (TableRow) keyString.get("side");

                      TableRow targetRow = new TableRow();

                      targetRow.set("partyID", Integer.valueOf(keyString.get("key").toString()));
                      targetRow.set("accountNumber", mainList.get("ACCOUNT_NUMBER"));
                      targetRow.set("customerName", sideList.get("PARTY_NAME"));
                      targetRow.set("updatedDate",keyString.get("updatedDate"));

                      c.output(targetRow);
                  
            ));

            PCollection<TableRow> headerData = p.apply("ReadInvoice",BigQueryIO.readTableRows().from(options.getOrderHeaderAll()));

            PCollection<TableRow> pc934Collection = headerData.apply(Filter.by(
                     (TableRow t) -> 
                         String orgCode = t.get("SHIP_FROM_ORG_ID").toString();
                         if (orgCode.equals("934")) 
                             return true;
                         
                         return false;
                     
                    ));

            WithKeys<String, TableRow> soltoOrg = WithKeys.of(
                    (TableRow row) ->
                        String.format("%s#%s",
                            row.get("SOLD_TO_ORG_ID"),
                            row.get("CUST_ACCOUNT_ID")))
                    .withKeyType(TypeDescriptors.strings());

            PCollection<KV<String,TableRow>> customerHeaderAccount = pc934Collection.apply("WithKeys", soltoOrg);
            PCollection<KV<String,TableRow>> customerHeaderAll = finalResultCollection.apply("WithKeys", soltoOrg);

            PCollection<TableRow> secondResult  = CommonFunctions.innerJoinBQTbls("InnerJoin1",customerHeaderAll,customerHeaderAccount);

            @SuppressWarnings("serial")
            PCollection<TableRow> secondResultCollection =  secondResult.apply("Process", ParDo.of(new DoFn<TableRow, TableRow>() 
            
                  @ProcessElement
                  public void processElement(ProcessContext c) 
                  
                      TableRow keyString = c.element();

                      TableRow mainList = (TableRow) keyString.get("main");
                      TableRow sideList = (TableRow) keyString.get("side");

                      TableRow targetRow = new TableRow();

                      targetRow.set("orderNumber", mainList.get("ORDER_NUMBER"));
                      targetRow.set("headerId",  Integer.valueOf(mainList.get("HEADER_ID").toString()));
                      targetRow.set("partyID", Integer.valueOf(keyString.get("key").toString()));
                      targetRow.set("accountNumber", mainList.get("ACCOUNT_NUMBER"));
                      targetRow.set("customerName", sideList.get("PARTY_NAME"));
                      targetRow.set("updatedDate",keyString.get("updatedDate"));

                      c.output(targetRow);
                  
            ));

【参考方案1】：

很可能您的其中一个键为空。您可以通过不将此作为主键来解决此问题。主键不能为 NULL，或者，如果它们是复合主键，则不能包含 NULL。取而代之的是使其成为唯一索引。例如使用自动编号字段作为主键。