执行 java 类以更新 mysql 数据库时出现此错误
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 'usage = 6000 where user_id = 1 and api_id = 1'
at line 1
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstruct
orAccessorImpl.java:39)..
这是代码:
int u_id=1;
int a_id=1;
String url = "jdbc:mysql://localhost:3306/new_db";
String driver = "com.mysql.jdbc.Driver";
String userName = "root";
String password = "1234";
int APIusage = 0;
try {
Class.forName(driver).newInstance();
Connection conn = DriverManager.getConnection(url, userName, password);
String query = "update api_consume set usage = ? where user_id = ? and api_id = ?";
PreparedStatement preparedStmt = conn.prepareStatement(query);
preparedStmt.setInt(1, 6000);
preparedStmt.setInt(2, u_id);
preparedStmt.setInt(3, a_id);
// execute the java preparedstatement
preparedStmt.executeUpdate();
conn.close();
}
catch (Exception e) {
e.printStackTrace();
}
你能看看它,看看为什么会出现语法错误吗?谢谢