DataX-Oracle新增writeMode支持update

本文主要是介绍DataX-Oracle新增writeMode支持update，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

前言

第一步下载源码

第二步修改源码

1、Oraclewriter

2、WriterUtil

2.1、修改getWriteTemplate方法

2.2、新增onMergeIntoDoString与getStrings方法

3、CommonRdbmsWriter

3.1、修改startWriteWithConnection

3.2、修改doBatchInsert

3.3、修改fillPreparedStatement

第三步打包

第四步脚本修改

修改后jar包地址

前言

目前 DataX更新到datax_v202309版本还不能支持Oracle写入的update，只通过DataX只能修改源码。

原理：oracle 不支持类似 MySQL的 REPLACE INTO 和 INSERT … ON DUPLICATE KEY UPDATE，所以只支持 insert 配置项。要实现此功能，需要利用 Oracle 的 merge 语句，先来看下 merge 语法。

MERGE INTO [target-table] A USING [source-table sql] B 
ON([conditional expression] and [...]...) 
WHEN MATCHED THEN[UPDATE sql] 
WHEN NOT MATCHED THEN [INSERT sql]

第一步下载源码

地址：datax_v202309。

第二步修改源码

一共修改3个文件

1、Oraclewriter

找到该代码直接注释掉就行。

2、WriterUtil

2.1、修改getWriteTemplate方法

public static String getWriteTemplate(List<String> columnHolders, List<String> valueHolders, String writeMode, DataBaseType dataBaseType, boolean forceUseUpdate) {boolean update = writeMode.trim().toLowerCase().startsWith("update");boolean isWriteModeLegal = writeMode.trim().toLowerCase().startsWith("insert")|| writeMode.trim().toLowerCase().startsWith("replace")|| update;if (!isWriteModeLegal) {throw DataXException.asDataXException(DBUtilErrorCode.ILLEGAL_VALUE,String.format("您所配置的 writeMode:%s 错误. 因为DataX 目前仅支持replace,update 或 insert 方式. 请检查您的配置并作出修改.", writeMode));}// && writeMode.trim().toLowerCase().startsWith("replace")String writeDataSqlTemplate;if (forceUseUpdate || update) {//update只在mysql下使用if (dataBaseType == DataBaseType.MySql || dataBaseType == DataBaseType.Tddl) {writeDataSqlTemplate = new StringBuilder().append("INSERT INTO %s (").append(StringUtils.join(columnHolders, ",")).append(") VALUES(").append(StringUtils.join(valueHolders, ",")).append(")").append(onDuplicateKeyUpdateString(columnHolders)).toString();}//update在Oracle下使用else if (dataBaseType == DataBaseType.Oracle) {writeDataSqlTemplate = onMergeIntoDoString(writeMode, columnHolders, valueHolders) + "INSERT (" +StringUtils.join(columnHolders, ",") +") VALUES(" + StringUtils.join(valueHolders, ",") +")";}else {throw DataXException.asDataXException(DBUtilErrorCode.ILLEGAL_VALUE,String.format("当前数据库不支持 writeMode:%s 模式.", writeMode));}} else {//这里是保护,如果其他错误的使用了update,需要更换为replaceif (update) {writeMode = "replace";}writeDataSqlTemplate = new StringBuilder().append(writeMode).append(" INTO %s (").append(StringUtils.join(columnHolders, ",")).append(") VALUES(").append(StringUtils.join(valueHolders, ",")).append(")").toString();}return writeDataSqlTemplate;}

2.2、新增onMergeIntoDoString与getStrings方法

代码作用：对Oracle进行update的MERGE拼接

public static String onMergeIntoDoString(String merge, List<String> columnHolders, List<String> valueHolders) {String[] sArray = getStrings(merge);StringBuilder sb = new StringBuilder();sb.append("MERGE INTO %s A USING ( SELECT ");boolean first = true;boolean first1 = true;StringBuilder str = new StringBuilder();StringBuilder update = new StringBuilder();for (String columnHolder : columnHolders) {if (Arrays.asList(sArray).contains(columnHolder)) {if (!first) {sb.append(",");str.append(" AND ");} else {first = false;}str.append("TMP.").append(columnHolder);sb.append("?");str.append(" = ");sb.append(" AS ");str.append("A.").append(columnHolder);sb.append(columnHolder);}}for (String columnHolder : columnHolders) {if (!Arrays.asList(sArray).contains(columnHolder)) {if (!first1) {update.append(",");} else {first1 = false;}update.append(columnHolder);update.append(" = ");update.append("?");}}sb.append(" FROM DUAL ) TMP ON (");sb.append(str);sb.append(" ) WHEN MATCHED THEN UPDATE SET ");sb.append(update);sb.append(" WHEN NOT MATCHED THEN ");return sb.toString();}public static String[] getStrings(String merge) {merge = merge.replace("update", "");merge = merge.replace("(", "");merge = merge.replace(")", "");merge = merge.replace(" ", "");return merge.split(",");}

3、CommonRdbmsWriter

3.1、修改startWriteWithConnection

        // 替换原先的代码块public void startWriteWithConnection(RecordReceiver recordReceiver, TaskPluginCollector taskPluginCollector, Connection connection) {this.taskPluginCollector = taskPluginCollector;List<String> columns = new LinkedList<>();if (this.dataBaseType == DataBaseType.Oracle && writeMode.trim().toLowerCase().startsWith("update") ) {String merge = this.writeMode;String[] sArray = WriterUtil.getStrings(merge);this.columns.forEach(column->{if (Arrays.asList(sArray).contains(column)) {columns.add(column);}});this.columns.forEach(column->{if (!Arrays.asList(sArray).contains(column)) {columns.add(column);}});}columns.addAll(this.columns);// 用于写入数据的时候的类型根据目的表字段类型转换this.resultSetMetaData = DBUtil.getColumnMetaData(connection, this.table, StringUtils.join(columns, ","));// 写数据库的SQL语句calcWriteRecordSql();List<Record> writeBuffer = new ArrayList<Record>(this.batchSize);int bufferBytes = 0;try {Record record;while ((record = recordReceiver.getFromReader()) != null) {if (record.getColumnNumber() != this.columnNumber) {// 源头读取字段列数与目的表字段写入列数不相等，直接报错throw DataXException.asDataXException(DBUtilErrorCode.CONF_ERROR,String.format("列配置信息有错误. 因为您配置的任务中，源头读取字段数:%s 与 目的表要写入的字段数:%s 不相等. 请检查您的配置并作出修改.",record.getColumnNumber(),this.columnNumber));}writeBuffer.add(record);bufferBytes += record.getMemorySize();if (writeBuffer.size() >= batchSize || bufferBytes >= batchByteSize) {doBatchInsert(connection, writeBuffer);writeBuffer.clear();bufferBytes = 0;}}if (!writeBuffer.isEmpty()) {doBatchInsert(connection, writeBuffer);writeBuffer.clear();bufferBytes = 0;}} catch (Exception e) {throw DataXException.asDataXException(DBUtilErrorCode.WRITE_DATA_ERROR, e);} finally {writeBuffer.clear();bufferBytes = 0;DBUtil.closeDBResources(null, null, connection);}}

3.2、修改doBatchInsert

 protected void doBatchInsert(Connection connection, List<Record> buffer)throws SQLException{PreparedStatement preparedStatement = null;try {connection.setAutoCommit(false);preparedStatement = connection.prepareStatement(this.writeRecordSql);if (this.dataBaseType == DataBaseType.Oracle && !"insert".equalsIgnoreCase(this.writeMode)) {String merge = this.writeMode;String[] sArray = WriterUtil.getStrings(merge);for (Record record : buffer) {List<Column> recordOne = new ArrayList<>();for (int j = 0; j < this.columns.size(); j++) {if (Arrays.asList(sArray).contains(this.columns.get(j))) {recordOne.add(record.getColumn(j));}}for (int j = 0; j < this.columns.size(); j++) {if (!Arrays.asList(sArray).contains(this.columns.get(j))) {recordOne.add(record.getColumn(j));}}for (int j = 0; j < this.columns.size(); j++) {recordOne.add(record.getColumn(j));}for (int j = 0; j < recordOne.size(); j++) {record.setColumn(j, recordOne.get(j));}preparedStatement = fillPreparedStatement(preparedStatement, record);preparedStatement.addBatch();}}else {for (Record record : buffer) {preparedStatement = fillPreparedStatement(preparedStatement, record);preparedStatement.addBatch();}}preparedStatement.executeBatch();connection.commit();}catch (SQLException e) {LOG.warn("回滚此次写入, 采用每次写入一行方式提交. 因为: {}", e.getMessage());connection.rollback();doOneInsert(connection, buffer);}catch (Exception e) {throw DataXException.asDataXException(DBUtilErrorCode.WRITE_DATA_ERROR, e);}finally {DBUtil.closeDBResources(preparedStatement, null);}}

3.3、修改fillPreparedStatement

  protected PreparedStatement fillPreparedStatement(PreparedStatement preparedStatement, Record record)throws SQLException{for (int i = 0; i < record.getColumnNumber(); i++) {int columnSqltype = this.resultSetMetaData.getMiddle().get(i);String typeName = this.resultSetMetaData.getRight().get(i);preparedStatement = fillPreparedStatementColumnType(preparedStatement, i,columnSqltype, typeName,record.getColumn(i));}return preparedStatement;}

第三步打包

1、只需要在idea里面打包修改的两个程序就可以

2、打包成功后获取两个jar包

3、将包替换到datax的插件里面

将oraclewriter-0.0.1-SNAPSHOT.jar替换到datax\plugin\writer\oraclewriter

将plugin-rdbms-util-0.0.1-SNAPSHOT.jar替换到datax\plugin\writer\oraclewriter\libs

第四步脚本修改

{"job": {"setting": {"speed": {"byte": 1048576},"errorLimit": {"record": 0,"percentage": 0.02}},"content": [{"reader": {"name": "mysqlreader","parameter": {"username": "${r_username}","password": "${r_password}","connection": [{	   "querySql": ["SELECT f_year,f_code,f_name,f_order FROM tableName"],"jdbcUrl": ["${r_jdbcUrl}"]}]}},"writer": {"name": "oraclewriter","parameter": {"writeMode": "update(f_year,f_code)","username": "${w_username}","password": "${w_password}","column": ["f_year","f_code","f_name","f_order"],"session": [],"preSql": [],"connection": [{"jdbcUrl": "${w_jdbcUrl}","table": ["tableName"]}]}}		   }]}
}

参数 "writeMode": "update(f_year,f_code)" 里面f_year,f_code就是主键，参数上不要加/"

update(\"f_year\",\"f_code\")这样是拼不上sql的，这个问题调试了好久才解决。

这时候运行就成功了

参考文章DataX 二次开发支持 Oracle 更新数据https://blog.csdn.net/xch_yang/article/details/128250190?utm_medium=distribute.pc_relevant.none-task-blog-2~default~baidujs_baidulandingword~default-0-128250190-blog-106881907.235%5Ev43%5Epc_blog_bottom_relevance_base8&spm=1001.2101.3001.4242.1&utm_relevant_index=3Datax oracle 支持增量并且支持全量更新https://blog.csdn.net/weixin_41250031/article/details/122615271?spm=1001.2101.3001.6650.5&utm_medium=distribute.pc_relevant.none-task-blog-2~default~CTRLIST~Rate-5-122615271-blog-129723622.235%5Ev43%5Epc_blog_bottom_relevance_base8&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2~default~CTRLIST~Rate-5-122615271-blog-129723622.235%5Ev43%5Epc_blog_bottom_relevance_base8&utm_relevant_index=7