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This article will explain in detail about java connection navicat method, small make up feel quite practical, so share to everyone for a reference, hope you can have some harvest after reading this article.

In the actual use of applications, most of them need to use the database for data queries and operations, because the database supports powerful SQL statements, transactions and so on. The following describes how to use JDBC to provide APIs and databases for information delivery in Java applications.

First of all, you need to install MySQl database, install the installed database, establish the database, create tables, and also need to operate the database through JDBC.

Java provides by using JDBC API to operate the database, JDBC operation of different databases is only the difference in the way of connection, the use of JDBC applications and databases to establish contact after it can be operated.

Using JDBC requires the following:

:: Establishing a connection to the database

·Send SQL statements to connected databases

·Processing results returned by SQL statements

After the MySQL database service starts, you must first establish a connection to the database on the database server. Java uses JDBC to invoke the native JDBC-database driver to establish a connection to the corresponding database. Java runtime environment converts JDBC database driver into a special protocol used by DBMS (database management system) to realize interaction information with specific DBMS, as shown in the following figure:

There are two steps to establishing a connection to a database using the JDBC database driver:

(1) Loading JDBC-Database Driver

(2) Establish a connection with a specified database

First download JDBC-MySQL database driver, JDBC download URL:

https://dev.mysql.com/downloads/file/? id=474258。Unzip the downloaded zip file, find the mysql-connector-java-5.1.45-bin.jar file inside, and copy it to the JDK extension directory, for example, my D: StudyJava1.8.0jreliext directory.

At the same time, because there will be an additional JRE when installing JDK, it is best to copy the mysql-connector-java-5.1.45-bin.jar file to that directory, mine is D: StudyJRE1.8.0liext directory, to ensure that the environment is enabled in time to run the program, there will also be the required drivers.

Next is to load the JDBC-MySQL database driver, the code is as follows:

try { Class.forName("com.mysql.jdbc.Driver"); } catch (Excepton e) { }

MySQL database driver is encapsulated in the Driver class, package name com.mysql.jdbc, it is not a class in the Java runtime environment class library, so it needs to be placed in the extension directory of jre.

The DriverManager class in the java.sql package has two class methods (static methods) for establishing connections:

·Connection getConnection(java.lang.String,java.lang.String,java.lang.String)

·Connection getConnection(java.lang.String)

Find MySQL Notifier on your computer and run it, then right-click its icon in the taskbar and select MySQL57-Stopped-->Start to start the database.

Then open Navicat for MySQL, open the connection, establish a connection with the database server, right click on the connection name and select the "New Database" command, fill in the corresponding information in the pop-up dialog box, as shown below, and establish a database named Study.

After the database is established, right click "Table" under Study, select "New Table," fill in the corresponding column names and various attributes of column names,

Click Save, enter the table name to save, then double-click the table name, fill in the corresponding information, add a new row, click "+".

Next, use a small program to test the query operation of the database.

Create a Java project with the following code:

import java.sql.*; public class MysqlTest { public static void main (String[] args) { //load JDBC-MySQL driver try { Class.forName ("com.mysql.jdbc.Driver");} catch (Exception e) {} //Establish a connection with the database, where 3306 after the ip address is the port number, study is the database name, plus the user name and password.//Set useSSL to true.//If there are Chinese characters recorded in the table, add the characterEncoding parameter. The value is gb2312 or utf-8 Connection con = null; String uri = "jdbc:mysql://192.168.199.240:3306/study? user=root&password=****&useSSL=true&characterEncoding= utf-8 "; try { con = DriverManager.getConnection(uri); //connection code} catch (SQLException e) { System.out.println(e); } //Send SQL query statement try { Statement sql = con.createStatement(); //Declare and create SQL statement object ResultSet rs = sql.executeQuery ("SELECT * FROM test"); //Query test table System.out.println("Query result: "); while (rs.next()) { //Loop reads data from each row of test table and outputs String number = rs.getString(1); String name = rs.getString(2); Date date = rs.getDate(3); float height = rs.getFloat(4); System.out.printf("%s ",number); System.out.printf("%s ",name); System.out.printf("%s ",date); System.out.printf("%s ",height); System.out.println(); } con.close(); //Close database connection} catch (SQLException e) { System.out.println(e); } }}

Run this program and the output is as follows:

At this point, Java successfully connected to MySQL database and implemented sequential query.

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