java实现sql批量插入参数

背景:
 需要更新一些不规范的时间格式,如将某个时间格式化为yy-MM-dd,实际上为 yy-MM-dd hh:mm:ss,并且需要提供回滚脚本。

例如:规范化时间的脚本如下:

update test set test_date=substring(account_date,1,10) WHERE test_date>‘2017-06-01 00:00:00‘ AND test_date<‘2017-09-07 00:00:00‘

这个脚本是ok,但执行时受到影响的行数如果有几百条甚至上千条记录的话,回滚脚本怎么写呢?

模板如下:

update test set test_date= ‘‘ where id=‘‘;

1.首先,从test表中查出上述的参数:

select id,test_date from test where test_date>‘2017-06-01 00:00:00‘ AND test_date<‘2017-09-07 00:00:00‘

将结果导入到文本中,名为为param.txt

2.然后运行以下java程序,打印出可执行的回滚脚本


    private void insertData() throws IOException{        
        FileReader reader = new FileReader("D:\\document\\load\\data1.txt");
        BufferedReader br = new BufferedReader(reader);    
        String updateSql="update test set test_date= ‘‘ where id=‘‘;";
        String line = null;
        Integer count=0;
        String[] param=new String[2];
        String regexp = "\‘\‘";
        while((line = br.readLine()) != null) {
            param=line.split("\\\t");
            String first=updateSql.replaceFirst(regexp,"\‘"+param[1]+"\‘");
            String second=first.replaceFirst(regexp,"\‘"+param[0]+"\‘");
            System.out.println(second);
            count++;
        }
        br.close();
        reader.close();
    }

3.如果行数较多,需要打印到文件中(Console打印的记录数受限的)

 private void insertData() throws IOException{        
        FileReader reader = new FileReader("D:\\document\\load\\data1.txt");
        BufferedReader br = new BufferedReader(reader);    
        StringBuffer sbf=new StringBuffer();
        String updateSql="update test set test_date= ‘‘ where id=‘‘;";
        String line = null;
        Integer count=0;
        String[] param=new String[2];
        String regexp = "\‘\‘";
        while((line = br.readLine()) != null) {
            param=line.split("\\\t");
            String first=updateSql.replaceFirst(regexp,"\‘"+param[1]+"\‘");
            String second=first.replaceFirst(regexp,"\‘"+param[0]+"\‘");
            //System.out.println(second);
            sbf.append(second).append("\n");
            count++;
        }
        writeFile("D:\\document\\load\\rollback.sql", sbf);
        br.close();
        reader.close();
    }

    public void writeFile(String fileName,StringBuffer stf) 
              throws IOException {
                BufferedWriter writer = new BufferedWriter(new FileWriter(fileName));
                writer.write(stf.toString());                 
                writer.close();
            }

java实现sql批量插入参数

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