Java export data from MySQL concrete example _java

Source: Internet
Author: User
Tags stmt

Copy Code code as follows:

Import java.sql.Connection;
Import Java.sql.DriverManager;
Import Java.sql.ResultSet;
Import java.sql.Statement;

Import Java.io.BufferedReader;
Import Java.io.File;
Import Java.io.FileOutputStream;
Import Java.io.FileReader;
Import java.io.IOException;
Import Java.io.OutputStreamWriter;
Import java.sql.Connection;
Import Java.sql.DriverManager;
Import java.sql.PreparedStatement;
Import Java.sql.ResultSet;
Import java.sql.SQLException;
Import java.sql.Statement;


public class TestDB {

public static void Main (string[] args) {


Test (); Generating test data
Exp ();
EXP (0);
System.out.println (ReadText ("/opt/id.txt"));
}

/**
* Export Data
*/
public static void Exp () {

Connection Conn=null;

try {


Class.forName ("Com.mysql.jdbc.Driver"). newinstance ();
String Jdbcurl = "JDBC:MYSQL://127.0.0.1:3306/TEST?CHARACTERENCODING=GBK";
String jdbcusername = "root";
String Jdbcpassword = "MySQL";
Conn = Drivermanager.getconnection (Jdbcurl, "root", "MySQL");

SYSTEM.OUT.PRINTLN ("conn" +conn);

EXP (Conn);

catch (SQLException e) {
E.printstacktrace ();
}
catch (Instantiationexception e) {
TODO auto-generated Catch block
E.printstacktrace ();
catch (Illegalaccessexception e) {
TODO auto-generated Catch block
E.printstacktrace ();
catch (ClassNotFoundException e) {
TODO auto-generated Catch block
E.printstacktrace ();
}
Finally
{

try {
Conn.close ();
catch (SQLException e) {
TODO auto-generated Catch block
E.printstacktrace ();
}
}

}

public static void Exp (int startid) {

Connection Conn=null;

try {

Class.forName ("Com.mysql.jdbc.Driver"). newinstance ();
String Jdbcurl = "JDBC:MYSQL://127.0.0.1:3306/TEST?CHARACTERENCODING=GBK";
String jdbcusername = "root";
String Jdbcpassword = "MySQL";
Conn = Drivermanager.getconnection (Jdbcurl, Jdbcusername, Jdbcpassword);

SYSTEM.OUT.PRINTLN ("conn" +conn);

EXP (Conn,startid);

catch (SQLException e) {
E.printstacktrace ();
}
catch (Instantiationexception e) {
TODO auto-generated Catch block
E.printstacktrace ();
catch (Illegalaccessexception e) {
TODO auto-generated Catch block
E.printstacktrace ();
catch (ClassNotFoundException e) {
TODO auto-generated Catch block
E.printstacktrace ();
}
Finally
{

try {
Conn.close ();
catch (SQLException e) {
TODO auto-generated Catch block
E.printstacktrace ();
}
}

}

/**
* Export data starting from Startid
* @param Conn
* @param start_id
*/
public static void Exp (Connection conn,int start_id) {

int counter = 0;
int startid=start_id;
Boolean flag = true;
while (flag) {
Flag = false;
String SQL = "SELECT * from T_test WHERE id>"
+ Startid + "ORDER BY ID ASC LIMIT 50";

System.out.println ("sql===" + sql);
try {
Statement stmt = Conn.createstatement ();
ResultSet rs = stmt.executequery (SQL);

while (Rs.next ()) {
Flag = true;
int id = rs.getint ("id");
String title = rs.getstring ("title");
Startid = ID;

       counter++;

       writecontent (counter+ "--id--" +id+ "--title-" +title+ "\ r \ n", "d:\\", " Log.txt ", true);

       System.out.println ("i=" +counter+ "--id--" +id+ "--title-" +title);

     }
     rs.close ();
     stmt.close ();
   } catch (SQLException e) {
     e.printstacktrace ();
   }
  }

   writecontent ("" +startid, "d:\\", "ID.txt", false);

 }

 /**
   * Export data within one hour
   * @param conn
   */

  Public static void Exp (Connection conn) {

   int counter = 0;
  //within one hour of data
   Long timestamp = System.currenttimemillis ()-(* * 1000);
   Boolean flag = true;
   while (flag) {
    flag = false;
    String Sql = "SELECT * from T_test WHERE createtime>"
      + timestamp + "LIMIT";

    System.out.println ("sql===" + sql);
    try {
     Statement stmt = Conn.createstatement ();
     ResultSet rs = stmt.executequery (SQL);
     while (Rs.next ()) {
      flag = true;
      int id = rs.getint ("id");
      String title = rs.getstring ("title");
      Long lastmodifytime = Rs.getlong ("Createtime");
      timestamp = lastmodifytime;

counter++;

System.out.println ("i=" +counter+ "--id--" +id+ "--title-" +title);

}
Rs.close ();
Stmt.close ();
catch (SQLException e) {
E.printstacktrace ();
}
}

}


public static void Test () {

Connection Conn=null;

   try {

    class.forname ("Com.mysql.jdbc.Driver"). Newinstance ()
    String jdbcurl = "JDBC:MYSQL://127.0.0.1:3306/TEST?CHARACTERENCODING=GBK";
    String jdbcusername = "root";
    String jdbcpassword = "MySQL";
    Conn = drivermanager.getconnection (Jdbcurl, Jdbcusername, Jdbcpassword);

    System.out.println ("conn" +conn);

    for (int i=1;i<=10000;i++)
    {
     Add (Conn, " Testtitle "+i+"-"+system.currenttimemillis ()");
   }

catch (SQLException e) {
E.printstacktrace ();
}
catch (Instantiationexception e) {
TODO auto-generated Catch block
E.printstacktrace ();
catch (Illegalaccessexception e) {
TODO auto-generated Catch block
E.printstacktrace ();
catch (ClassNotFoundException e) {
TODO auto-generated Catch block
E.printstacktrace ();
}
Finally
{

try {
Conn.close ();
catch (SQLException e) {
TODO auto-generated Catch block
E.printstacktrace ();
}
}

}

public static void Add (Connection conn,string title)
{
PreparedStatement pstmt = null;
String insert_sql = "INSERT into T_test (title,createtime) VALUES (?,?)";

System.out.println ("sql=" +insert_sql);
try {
pstmt = Conn.preparestatement (Insert_sql);
Pstmt.setstring (1,title);
Pstmt.setlong (2,system.currenttimemillis ());
int ret = Pstmt.executeupdate ();

catch (SQLException e) {
TODO auto-generated Catch block
E.printstacktrace ();
}
finally{
try {
Pstmt.close ();
catch (SQLException e) {
TODO auto-generated Catch block
E.printstacktrace ();
}
}

}

/**
* Write content to file
*
* @param number
* @param filename
* @return
*/
public static Boolean writecontent (string C, string dirname,string Filename,boolean isappend) {

File F=new file (dirname);
if (!f.exists ())
{
F.mkdirs ();
}

try {
FileOutputStream fos = new FileOutputStream (dirname+file.separator+filename,isappend);
OutputStreamWriter writer = new OutputStreamWriter (FOS);
Writer.write (c);
Writer.close ();
Fos.close ();
catch (IOException e) {
E.printstacktrace ();
return false;
}
return true;
}


/**
* Read content from File
*
* @param filename
* @return
*/
public static string ReadText (string filename) {
String content = "";
try {
File File = new file (filename);
if (file.exists ()) {
FileReader FR = new FileReader (file);
BufferedReader br = new BufferedReader (FR);
String str = "";
String newline = "";
while (str = Br.readline ())!= null) {
Content + + newline + str;
newline = "\ n";
}
Br.close ();
Fr.close ();
}
catch (IOException e) {
E.printstacktrace ();
}
return content;
}
}

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