在数据插入MySQL之前,我正在使用下面的代码进行检查。不过,我得到如下错误尝试向MySQL中插入数据时获取错误
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'WHERE NOT EXISTS (SELECT * FROM movie_title WHERE title = 'ABC')' at line 1
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
这里我的代码
public void checkAndAdd(String movieTitle) throws Exception {
// TODO Auto-generated method stub
DatabaseConnection db=new DatabaseConnection();
Connection connect=db.getConnection();
String sql="INSERT INTO movie_title(title) VALUES (?) WHERE NOT EXISTS (SELECT * FROM movie_title WHERE title = ?)";
PreparedStatement ps=connect.prepareStatement(sql);
ps.setString(1,movieTitle);
ps.setString(2,movieTitle);
ps.executeUpdate();
connect.close();
ps.close();
}
编辑
String sql=" IF NOT EXISTS(SELECT * FROM movie_title WHERE title = ?) INSERT INTO movie_title (title) VALUES (?) ";
如何找到你的问题:以你在Java中执行SQL,将其复制到MySQL并运行它。当mysql给你一个错误时,调试你的SQL – mmcrae