为什么此PreparedStaement会引发mysql错误?

我正在通过jdbc连接插入mysql数据库,该连接可以完美连接,如果我执行PreparedStatement时,Tomcat会抛出一个SQL错误,提示以下内容:

java.sql.SQLSyntaxErrorException: 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 '?,?,?)' at line 1

问题是,当我通过一条语句进行查询时,它将执行查询而没有任何问题,这使我怀疑该错误实际上在PreparedSatement中。我在这里留下代码。

@Override
public void save(Planet planet) throws SQLException {
    String namePlanet = planet.getName();
    float massplanet = planet.getMass();
    boolean habitablePlanet = planet.isHabitable();
    sql = "INSERT INTO planeta (nom,massa,habitable) VALUES (?,?)";
    PreparedStatement preparedStatement = conn.prepareStatement(sql);
    preparedStatement.setString(1,namePlanet);
    preparedStatement.setfloat(2,massplanet);
    preparedStatement.setBoolean(3,habitablePlanet);
    preparedStatement.executeUpdate(sql);
}

我还将保留带有preparedstatement的代码,因此您可以看到它确实有效。

@Override
public void save(Planet planet) throws SQLException {
    String namePlanet = planet.getName();
    float massplanet = planet.getMass();
    boolean habitablePlanet = planet.isHabitable();
    sql = "insert into planeta(nom,habitable) value('" + namePlanet + "'," + massplanet + "," + habitablePlanet + ")";
    stmt.executeUpdate(sql);

}

请耐心等待我,我是一名学生,在此先感谢。

weilili123 回答:为什么此PreparedStaement会引发mysql错误?

就像@Jens在评论中告诉我,我必须不带参数调用executeUpdate()

再次感谢@Jens !!

那是正确的代码:

@Override
public void save(Planet planet) throws SQLException {
    String namePlanet = planet.getName();
    float massPlanet = planet.getMass();
    boolean habitablePlanet = planet.isHabitable();
    sql = "INSERT INTO planeta (nom,massa,habitable) VALUES (?,?,?)";
    PreparedStatement preparedStatement = conn.prepareStatement(sql);
    preparedStatement.setString(1,namePlanet);
    preparedStatement.setFloat(2,massPlanet);
    preparedStatement.setBoolean(3,habitablePlanet);
    preparedStatement.executeUpdate(); // <--- Here was the error!!

}

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