小编Raz*_*r22的帖子

如果buyid(主键)是特定值,我正在尝试更新列量.

UPDATE portfolio set amount=40 WHERE buyid=3

我使用JDBC和MySql,每次我尝试执行语句时都会遇到以下异常:

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException:您的SQL语法中有错误; 检查与您的MySQL服务器版本对应的手册,以便在第1行的'buyid = 3'附近使用正确的语法

表结构组合:

buyid int
username varchar
stockname varchar
priceperstock float
amount int

Javasourcecode:

public void sellStock(int buyid, int amount, float currentprice, String user) {

...

    try {
        stmt = this.conn.createStatement();
        System.out.println(fetchedamount);
        System.out.println("UPDATE portfolio
                            SET amount=" + fetchedamount
                        + " WHERE buyid=" + buyid);

        stmt.execute("UPDATE stockman.portfolio
                      SET amount=" + fetchedamount
                   + "WHERE buyid=" + buyid+"");
        // update capital
        newmoney = amount * currentprice + oldmoney;

    } catch (SQLException ee) { …