到目前为止，我正在尝试使用PHP在数据库上创建表，但是我设法使用PHP创建了数据库，但无法创建表/表

Question

<?PHP

    try{
        $handler = new PDO($servername, $username, $password);
        $handler->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
        $sql = "CREATE TABLE user_details ( 
            id INT NOT NULL AUTO_INCREMENT,
            email VARCHAR(30) NOT NULL,
            fullname VARCHAR(30) NOT NULL,
            username VARCHAR(30) NOT NULL,
            password VARCHAR(30)  NOT NULL,
            gender ENUM('male','female','other','')  NOT NULL , PRIMARY KEY (id)) 
            ENGINE = InnoDB
            )";
        echo "Sucessfullll";
        $handler->exc($sql);
    } catch (PDOException $msg){
        echo $msg->getMessage();
        die();
    }
?>

Answer 1

You have an extra unmatched parentheses )

$sql = "CREATE TABLE user_details ( 
           id INT NOT NULL AUTO_INCREMENT,
           email VARCHAR(30) NOT NULL,
           fullname VARCHAR(30) NOT NULL,
           username VARCHAR(30) NOT NULL,
           password VARCHAR(30)  NOT NULL,
           gender ENUM('male','female','other','')  NOT NULL ,
           PRIMARY KEY (id)
      ) ENGINE = InnoDB )";

Should be

$sql = "CREATE TABLE user_details ( 
           id INT NOT NULL AUTO_INCREMENT,
           email VARCHAR(30) NOT NULL,
           fullname VARCHAR(30) NOT NULL,
           username VARCHAR(30) NOT NULL,
           password VARCHAR(30)  NOT NULL,
           gender ENUM('male','female','other','')  NOT NULL ,
           PRIMARY KEY (id)
      ) ENGINE = InnoDB";

You also might need the length for the INT, I forget.

INDEXES

I always do my id's like this id INT(10) UNSINGED NOT NULL AUTO_INCREMENT because well no one like having a negative ID. And I would make UNIQUE(username) And UNIQUE(email) and maybe an INDEX(fullname) .

Indexes depend on what you plan on searching, the more indexes you have the long it takes to insert and update records. But for your average website it's pretty unnoticeable.

If you plan on inserting 10's of thousands of rows at a time, you would want to be more careful with indexes, because for each index it takes a bit extra time to compile them when modifying the data.

NAMING CONVENTIONS

Your field names look good, no plurals no casing. The only thing I would change here is name the table just users , I usually pluralize tables, and use _ as a way to mark a junction table, or a table that ties 2 tables together with a Many To Many relationship. So for example I would have users and addresses and then a table that joined them users_addresses .

If it's a table with a One to many, I will do a non-plural for the one and a plural for the many. So if each user could have many uploads. One to Many, I would name it like user_uploads . That way I can see what kind of relationship it is without opening up PHPmyAdmin or trying to remember how I set it up.

I just wanted to mention that, because the name you have going by my naming conventions, it would be a table with details in it with a user_id foreign key.

I should say everyone does naming conventions a bit differently the main thing is to name things for a reason, and be consistent.

last thing

This is just my Opinion, but I find it better to connect this way:

$options = [
     PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
     PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC
];

$handler = new PDO($servername, $username, $password, $options);

By sending it as options, it will throw an exception when you fail to connect. Otherwise you haven't set the mode until after the initial connection. And probably about 90% of the time I use associative arrays for my return, so you can set that too.

cheers!

Answer 2

I'm not sure what value you have stored in $servername variable. If you are storing just the IP address or hostname, then it's wrong.

The first argument to the PDO constructor is a Data Source Name ( dsn ). An example of a MySQL DSN is:

$dsn = 'mysql:dbname=testdb;host=127.0.0.1';
$handler = new PDO($dsn, $username, $password);

See http://php.net/manual/en/pdo.construct.php