17

次のコードがあります。

$db_host = 'localhost';
$db_port = '3306';
$db_username = 'root';
$db_password = 'root';
$db_primaryDatabase = 'dsl_ams';

// Connect to the database, using the predefined database variables in /assets/repository/mysql.php
$dbConnection = new mysqli($db_host, $db_username, $db_password, $db_primaryDatabase);

// If there are errors (if the no# of errors is > 1), print out the error and cancel loading the page via exit();
if (mysqli_connect_errno()) {
    printf("Could not connect to MySQL databse: %s\n", mysqli_connect_error());
    exit();
}

$queryCreateUsersTable = "CREATE TABLE IF NOT EXISTS `USERS` (
    `ID` int(11) unsigned NOT NULL auto_increment,
    `EMAIL` varchar(255) NOT NULL default '',
    `PASSWORD` varchar(255) NOT NULL default '',
    `PERMISSION_LEVEL` tinyint(1) unsigned NOT NULL default '1',
    `APPLICATION_COMPLETED` boolean NOT NULL default '0',
    `APPLICATION_IN_PROGRESS` boolean NOT NULL default '0',
    PRIMARY KEY  (`ID`)
)";

if(!$dbConnection->query($queryCreateUsersTable)){
    echo "Table creation failed: (" . $dbConnection->errno . ") " . $dbConnection->error;
}

どの出力...

Table creation failed: (1050) Table '`dsl_ams`.`USERS`' already exists

私が理解できないのはIF NOT EXISTS、そのテーブルが既に存在する場合、SQL クエリの実行をキャンセルすることは想定されていないということです。つまり、テーブルが存在する場合、その if ステートメントを終了し、何もエコーアウトせず、クエリを実行しようとしないでください。

ユーザーに何も出力せずに「存在しない場合はテーブルを作成する」ための最良の方法を見つけようとしています。

4

5 に答える 5

23

Try this

$query = "SELECT ID FROM USERS";
$result = mysqli_query($dbConnection, $query);

if(empty($result)) {
                $query = "CREATE TABLE USERS (
                          ID int(11) AUTO_INCREMENT,
                          EMAIL varchar(255) NOT NULL,
                          PASSWORD varchar(255) NOT NULL,
                          PERMISSION_LEVEL int,
                          APPLICATION_COMPLETED int,
                          APPLICATION_IN_PROGRESS int,
                          PRIMARY KEY  (ID)
                          )";
                $result = mysqli_query($dbConnection, $query);
}

This checks to see if anything is in the table and if it returns NULL you don't have a table.

Also there is no BOOLEAN datatype in mysql, you should INT and just set it to 1 or 0 when inserting into the table. You also don't need single quotes around everything, just when you are hardcoding data into the query.

Like this...

$query = "INSERT INTO USERS (EMAIL, PASSWORD, PERMISSION_LEVEL, APPLICATION_COMPLETED, APPLICATION_IN_PROGRESS) VALUES ('foobar@foobar.com', 'fjsdfbsjkbgs', 0, 0, 0)";
于 2013-05-15T00:19:20.723 に答える