Java - Mysql - 多重查询 [英] Java - Mysql - Multiple query

问题描述

String qLink = "";

String qLink = "";

                        qLink = "INSERT INTO trackgps.queclinklogs(Supplier,NtwProtocol,IMEI,log,DBTIME)" +
                                "VALUES"                    +
                                "("                         +
                                "'" + supplier              + "',"+
                                "'" + protocol              + "',"+
                                "'" + failedQIMEI           + "',"+
                                "'" + failedQLog            + "',"+
                                "'" + currentQuecTimestamp  + "'" +
                                "),"                        +
                                "("                         +
                                "'" + supplier              + "'" + "," +
                                "'" + protocol              + "'" + "," +
                                "'" + QuecLinkIMEI          + "'" + "," +
                                "'" + data2                 + "'" + "," +
                                "'" + currentQuecTimestamp  + "'" +
                                ")";    


                        Statement stmtLink = connQ.createStatement();
                        stmtLink.execute(qLink);
                        stmtLink.close();

String bytesconsumption = "";

String bytesconsumption = "";

                    bytesconsumption = "INSERT INTO test_backoffice.carrierDataConsumption(IMEI,beginMonth,endMonth,dataConsumed,month,year) VALUES"    +
                                        "("                                                                                                             +
                                        "'"+ QuecLinkIMEI                                                                                   + "'" + "," +
                                        "NOW()"                                                                                                   + "," +
                                        "NOW()"                                                                                                   + "," +
                                        "'"+ totalBytesConsumed                                                                                  + "'," +
                                        "MONTH(NOW())"                                                                                            + "," +
                                        "YEAR(NOW())"                                                                                                   +
                                        ") ON DUPLICATE KEY UPDATE endMonth = NOW(), dataConsumed = dataConsumed + " + totalBytesConsumed;

                    Statement stmtbytesconsumption;

                    stmtbytesconsumption = connQ.createStatement();
                    stmtbytesconsumption.execute(bytesconsumption);
                    stmtbytesconsumption.close();

String qdebug = "";

String qdebug = "";

    qdebug = "INSERT INTO trackgps.rawdata(Module,SubModule,IMEI,listenerTime,msg)" +
            "VALUES"                    +
            "("                         +
            "'"+ "LISTENER TCP"         + "'" + "," +
            "'"+ SubMod                 + "'" + "," +
            "'"+ identifier             + "'" + "," +
            "'"+ listendatetime         + "'" + "," +
            "'"+ msg                    + "'" +
            ")";    

    Statement stmtqdebug = conn.createStatement();
    stmtqdebug.execute(qdebug);
    stmtqdebug.close();

有没有办法在一个 java 语句中执行这三个插入?而不是创建 3 个语句，其中 3 个执行和 3 个关闭?

Is there anyway to execute this three inserts in just one java statement? Instead of creating 3 Statements with 3 executes and 3 closes?

我还有其他问题，我应该使用 Statements 还是 PrepareStatements?

Other question I have, Should I use Statements or PrepareStatements?

推荐答案

您可以在一个语句上调用所有 3 个查询:

You can call all 3 queries on one statement:

Statement stmt = conn.createStatement();
stmt.executeUpdate(qLink);
stmt.executeUpdate(bytesconsumption);
stmt.executeUpdate(qdebug);
stmt.close();

在需要时使用 PreparedSatement 而不是 Statement:

Use PreparedSatement instead of Statement when you want:

• 使用不同的参数集多次执行相同的语句
• 不要关心参数格式，例如.如果 listendatetime 是 Timestamp 类型，您可以只使用 ps.setTimestamp(4, listendatetime) 和驱动程序在底层数据库上独立正确格式化它.

• to execute the same statement many times with different set of parameters
• don't take care about parameter formating, eg. if listendatetime is of type Timestamp, you can use just ps.setTimestamp(4, listendatetime) and a driver formats it properly independently on underlaying database.

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