CREATE DATABASE query using java jdbc and prepared statement returns syntax error

问题

I am trying to get Java to create a database using JDBC but I get a syntax error, despite the query being correct. If I write the name of a database into the code explicitly, for example, it works fine. Here's my code:

package mysql_manipulator;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;

public class Create {
    private static final String 
            driver = "com.mysql.jdbc.Driver",
            url = "jdbc:mysql://localhost",
            username = "dylan",
            password = "******";
    private String databaseName;

    public Create (){
        this.databaseName = null;
    }

    public String getDatabaseName() {
        return databaseName;
    }

    public void setDatabaseName(String databaseName) {
        this.databaseName = databaseName;
    }

    public void createDatabase(String databaseName){
        try {
            this.setDatabaseName(databaseName);        
            Class.forName(driver);
            Connection con = DriverManager.getConnection(url,username, 
                password);
            String query = "CREATE DATABASE ?";
            PreparedStatement preparedStmt = con.prepareStatement(query);
            preparedStmt.setString (1,this.getDatabaseName());
            preparedStmt.execute();
            preparedStmt.close();
            con.close();        
        }
        catch (Exception anException){
            System.out.println("Error: " + anException);
        }
    }
}

My Main Class

package mysql_manipulator;

public class Mysql_manipulator {
    public static void main(String[] args) {
        Create myObj = new Create();
        myObj.createDatabase("whatevs");        
    }    
}

The error

Error: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You  have an error in
your SQL syntax; check the manual that corresponds to your  MariaDB server version 
for the right syntax to use near ''whatevs'' at line 1

Huge thanks to anyone who knows why this isn't working - I've searched all over the web to no avail.

回答1:

You cannot have the database name as a bind variable -- you have to embed it in the query literal. Change your query into this instead:

String query = "CREATE DATABASE " + getDatabaseName();

You can also use a plain Statement (instead of PreparedStatement) for running this SQL.

回答2:

Conn = DriverManager.getConnection 
("jdbc:mysql://localhost/?user=root&password=rootpassword"); 
Statement s=Conn.createStatement(); 

int Result=s.executeUpdate("CREATE DATABASE databasename");

see

http://forums.mysql.com/read.php?39,99321,102211#msg-102211

Create MySQL database from Java

来源：https://stackoverflow.com/questions/31763214/create-database-query-using-java-jdbc-and-prepared-statement-returns-syntax-erro

标签

java

mysql

jdbc

prepared-statement