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JAVA-SQL语法错误_Java_Mysql_Jdbc - Fatal编程技术网

JAVA-SQL语法错误

JAVA-SQL语法错误,java,mysql,jdbc,Java,Mysql,Jdbc,我正在用Java创建一个方法。这是为了从数据库中检索消息,但我不断收到语法错误。有人能帮我吗 public static String retrieveMessages() { PreparedStatement pstmt; try { pstmt = connection.prepareStatement("SELECT * from tblEmail" + "INNERJOIN tblUser "

我正在用Java创建一个方法。这是为了从数据库中检索消息,但我不断收到语法错误。有人能帮我吗

public static String retrieveMessages()
{
    PreparedStatement pstmt;
    try
    {
        pstmt = connection.prepareStatement("SELECT * from  tblEmail"
                + "INNERJOIN tblUser "
                +  "ON tblUser.username = tblEmail.`from`"
                +  "WHERE tblUser.username = ?");

        pstmt.setString(1, user.Getuser());
        results = pstmt.executeQuery();

    }
    catch (SQLException e)
    {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    return (results.toString());

}
您需要添加空格(在
内部
之前和
其中
之前)。将查询拆分为多行不会将一行的结尾与下一行的开头分开

    pstmt = connection.prepareStatement("SELECT * from  tblEmail "
                                      + "INNER JOIN tblUser "
                                      +  "ON tblUser.username = tblEmail.`from` "
                                      +  "WHERE tblUser.username = ?");
当你写作时:

                                        "SELECT * from  tblEmail"
                                      + "INNER JOIN tblUser "
这与:

                                        "SELECT * from  tblEmailINNER JOIN tblUser "

t邮件
内部
之间以及
来自
其中

pstmt = connection.prepareStatement("SELECT * from  tblEmail "
                                          + "INNER JOIN tblUser "
                                          +  "ON tblUser.username = tblEmail.`from` "
                                          +  "WHERE tblUser.username = ?");

@Masud将编译,这不是问题。“但我一直有语法错误”发布错误怎么样?你可以让有相同错误的人在这里找到答案吗?这也会提高你得到更好答案的机会。@LuiggiMendoza,是的,我错了。。