MySQL/JAVA插入速度
因此，我正在NetBeans中为类开发一个MySQL/Java程序，帮助我们理解执行时间等等 因此，我创建了java程序，以便用户可以在6个表中的每个表中输入x个元组。所以我们必须输入125000个元组的数据。我只讨论了60000个元组的问题，当程序执行时，插入60000个元组大约需要30分钟 不用说，最终我将不得不在一个表中输入125000个元组，我需要知道如何使这个插入更快？有什么想法吗 多谢各位 布兰登 编辑： 代码MySQL/JAVA插入速度,java,mysql,insert,tuples,execution-time,Java,Mysql,Insert,Tuples,Execution Time,因此，我正在NetBeans中为类开发一个MySQL/Java程序，帮助我们理解执行时间等等 因此，我创建了java程序，以便用户可以在6个表中的每个表中输入x个元组。所以我们必须输入125000个元组的数据。我只讨论了60000个元组的问题，当程序执行时，插入60000个元组大约需要30分钟 不用说，最终我将不得不在一个表中输入125000个元组，我需要知道如何使这个插入更快？有什么想法吗 多谢各位 布兰登 编辑： 代码 使用PreparedStatement代替语句。它“预编译”SQL，以更
使用
PreparedStatement语句PreparedStatement由于许多原因，您可能会遇到插入速度慢的问题。我们需要了解一些代码以及mySQL数据库的设置。您可以尝试禁用autommit以避免每次插入都被单独提交。看，你会如何改变我所拥有的。也许只是在部门部分。你已经有了一个例子：。是的，我现在正在调查预处理的报表。我看到的大多数示例都为每个独立列输入数据。要从语句传输到PreparedStatement的任何链接或示例
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package program2;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;
import java.util.Random;
public class Program2 {
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
// Variables
int takesnum=0;
int instructornum=0;
int coursenum = 0;
int studentnum = 0;
int count = 0;
int departmentnum =0;
int counts= 0;
int minimum=0;
int x=0;
int teachesnum=0;
// Variables
//Connection to the database
Connection conn = null;
String url = "jdbc:mysql://localhost:3306/";
String dbName = "university2";
String Driver = "com.mysql.jdbc.Driver";
// Change the userName & password to what ever your credentials are.
String userName = "root";
String password = "121089bn";
//Connection to the database
try {
InputStreamReader istream = new InputStreamReader(System.in);
BufferedReader MyReader = new BufferedReader(istream);
Class.forName(Driver).newInstance();
conn = DriverManager.getConnection(url+dbName,userName,password);
System.out.println("Connected");
// Ask the user how many tuples in department table.
System.out.println("How many tuples would you like to create in Department Table?");
// Takes in as string the number then parse it to an int.
String dept = MyReader.readLine();
departmentnum = Integer.parseInt(dept);
// ****************** Department Table ******************//
while (count < departmentnum)
{
Statement st = conn.createStatement();
// Counts keeps the counter so the Primary Key is unique.
st.executeUpdate("Insert into department (dept_name, building, budget) values ('Dept "+counts+"', 'Voigt', '1200')");
count++;
counts++;
}
// ****************** Student Table ******************//
count=0;
counts=0;
System.out.println("How many tuples would you like to create in Student Table?");
String student = MyReader.readLine();
studentnum = Integer.parseInt(student);
while (count < studentnum)
{
int z=0;
int credit=128;
Random ran = new Random();
int range = departmentnum - minimum;
x = ran.nextInt(range) + minimum;
Random random = new Random();
int totcred = credit - minimum;
z = random.nextInt(totcred) + minimum;
Statement st = conn.createStatement();
st.executeUpdate("Insert into student (id, name, dept_name,tot_cred) select '"+counts+"', 'Student "+counts+"', dept_name, '"+z+"' from department where dept_name='Dept "+x+"'");
count++;
counts++;
}
// ****************** Course Table ******************//
x=0;
count=0;
counts=0;
System.out.println("How many tuples would you like to create in Course Table?");
String course = MyReader.readLine();
coursenum = Integer.parseInt(course);
while (count < coursenum)
{
Random ran = new Random();
int range = departmentnum - minimum;
x = ran.nextInt(range) + minimum;
int credit=5;
int z=0;
Random random = new Random();
int totcred = credit - minimum;
z = random.nextInt(totcred) + minimum;
Statement st = conn.createStatement();
st.executeUpdate("Insert into course (course_id, title, dept_name,credits) select '"+counts+"', 'Computer Science "+counts+"', dept_name, '"+z+"' from department where dept_name='Dept "+x+"'");
count++;
counts++;
}
// ****************** Instructor Table ******************//
x=0;
count=0;
counts=0;
System.out.println("How many tuples would you like to create in Instructor Table?");
String instructor = MyReader.readLine();
instructornum = Integer.parseInt(instructor);
while (count < instructornum)
{
Random ran = new Random();
int range = departmentnum - minimum;
x = ran.nextInt(range) + minimum;
Statement st = conn.createStatement();
st.executeUpdate("Insert into instructor (id, name, dept_name,salary) select '"+counts+"', 'Instructor "+counts+"', dept_name, '10000' from department where dept_name='Dept "+x+"'");
count++;
counts++;
}
// ****************** Teaches Table ******************//
x=0;
count=0;
counts=0;
System.out.println("How many tuples would you like to create in Teaches Table?");
String teaches = MyReader.readLine();
teachesnum = Integer.parseInt(teaches);
while (count < teachesnum)
{
Random ran = new Random();
int range = instructornum - minimum;
x = ran.nextInt(range) + minimum;
Random random = new Random();
int courserange = coursenum - minimum;
int y = random.nextInt(courserange) + minimum;
int g = 100;
Random r = new Random();
int f = g - minimum;
int h = r.nextInt(f) + minimum;
int l = 100;
Random random1 = new Random();
int j = l - minimum;
int k = random1.nextInt(j) + minimum;
Statement st = conn.createStatement();
st.executeUpdate("Insert into teaches (id, course_id, semester, year) select id, course_id, 'Spr "+h+"', '20"+k+"' from course, instructor where instructor.id='"+x+"' and course.course_id='"+y+"'");
count++;
counts++;
}
// ****************** Takes Table ******************//
x=0;
count=0;
counts=0;
System.out.println("How many tuples would you like to create in Takes Table?");
String takes = MyReader.readLine();
takesnum = Integer.parseInt(takes);
while (count < takesnum)
{
Random ran = new Random();
int range = studentnum - minimum;
x = ran.nextInt(range) + minimum;
Random random = new Random();
int courserange = coursenum - minimum;
int y = random.nextInt(courserange) + minimum;
int g = 100;
Random r = new Random();
int f = g - minimum;
int h = r.nextInt(f) + minimum;
int l = 100;
Random random1 = new Random();
int j = l - minimum;
int k = random1.nextInt(j) + minimum;
Statement st = conn.createStatement();
st.executeUpdate("Insert into takes (id, course_id, semester, year, grade) select id, course_id, 'Spr "+h+"', '20"+k+"', 'B' from course, student where student.id='"+x+"' and course.course_id='"+y+"'");
count++;
counts++;
}
conn.close();
}
catch (Exception e) {
System.err.println("Error");
System.err.println(e.getMessage());
}
}
}
drop database university2;
create database university2;
use university2;
create table department
(dept_name varchar(20) primary key,
building varchar(15),
budget numeric(12,2)
);
create table student
(ID int,
name varchar(20) not null,
dept_name varchar(20),
tot_cred numeric(10,0),
primary key (ID),
foreign key (dept_name) references department(dept_name)
);
create table course
(course_id int,
title varchar(50),
dept_name varchar(15),
credits numeric(2,0),
primary key (course_id),
foreign key (dept_name) references department(dept_name)
);
create table instructor
(ID int,
name varchar(20) not null,
dept_name varchar(20),
salary numeric(8,2),
primary key (ID),
foreign key (dept_name) references department(dept_name)
);
create table teaches
(ID int,
course_id int,
semester varchar(6),
year numeric(4,0),
primary key (ID, course_id, semester, year),
foreign key (course_id) references course(course_id)
on delete cascade,
foreign key (ID) references instructor(ID)
on delete cascade
);
create table takes
(ID int,
course_id int,
semester varchar(6),
year numeric(4,0),
grade varchar(2),
primary key (ID, course_id, semester, year),
foreign key (course_id) references course(course_id)
on delete cascade,
foreign key (ID) references student(ID)
on delete cascade
);