插入使用Where子句

Question

我在用where子句插入数据时有问题。以下是查询：

    $hi= "INSERT INTO user_detail (email, looking, username, profession, experience,
         current_work, state, job_type, about, college, diploma, department)
             VALUES ('$email', '$looking', '$username', '$profession','$experience',
     '$current_work', '$state', '$job_type', '$about', '$college', '$diploma', '$department')
 WHERE s='$username'";

它向我显示了错误：

您的SQL语法出现了错误；请检查与您的MySQL服务器版本相对应的手册，以便在第1行使用“WHERE=‘aniket276’”附近的正确语法。

Answer 1

使用MySQL更新

就像这样：-

UPDATE user_detail SET email='$email' WHERE s='$username';

如果要使用WHERE子句更改所选记录中字段的值，则应该使用UPDATE。

Answer 2

insert中的WHERE子句不会产生任何意义。

如果要向数据库中添加新行，则不需要WHERE子句，因为没有可以引用的现有行。

如果要更新现有行，则不应使用INSERT语句，而应使用UPDATE语句。

Answer 3

插入没有WHERE子句。

如果您只想为特定的用户名插入一行，那么最好在您的调用php脚本中这样做。

如果要修改特定用户名的现有行，则需要使用update语句：

UPDATE user_detail
SET email = '$email', 
    looking = '$looking', 
    username = '$username', 
    profession = '$profession', 
    experience = '$experience', 
    current_work = '$current_work', 
    state = '$state', 
    job_type = '$job_type', 
    about = '$about', 
    college = '$college', 
    diploma = '$diploma', 
    department = '$department'
WHERE s = '$username'

如果不存在行，则要插入行，但如果行存在，则可以进行插入/对重复键的更新(假设用户名的s列上有唯一索引)：-

INSERT INTO user_detail (s,
                        email, 
                        looking, 
                        username, 
                        profession, 
                        experience, 
                        current_work, 
                        state, 
                        job_type, 
                        about, 
                        college, 
                        diploma, 
                        department) 
VALUES ('$username',
        '$email', 
        '$looking', 
        '$username', 
        '$profession', 
        '$experience', 
        '$current_work', 
        '$state', 
        '$job_type', 
        '$about', 
        '$college', 
        '$diploma', 
        '$department') 
ON DUPLICATE KEY UPDATE email = VALUES(email), 
                        looking = VALUES(looking), 
                        username = VALUES(username), 
                        profession = VALUES(profession), 
                        experience = VALUES(experience), 
                        current_work = VALUES(current_work), 
                        state = VALUES(state), 
                        job_type = VALUES(job_type), 
                        about = VALUES(about), 
                        college = VALUES(college), 
                        diploma = VALUES(diploma), 
                        department = VALUES(department)