mysqli::prepare

mysqli_prepare

(PHP 5)

mysqli::prepare -- mysqli_prepare — Prepare an SQL statement for execution

Beschreibung

Objektorientierter Stil

mysqli_stmt mysqli::prepare ( string $query )

Prozeduraler Stil

mysqli_stmt mysqli_prepare ( mysqli $link , string $query )

Prepares the SQL query, and returns a statement handle to be used for further operations on the statement. The query must consist of a single SQL statement.

The parameter markers must be bound to application variables using mysqli_stmt_bind_param() and/or mysqli_stmt_bind_result() before executing the statement or fetching rows.

Parameter-Liste

link

Nur bei prozeduralem Aufruf: Ein von mysqli_connect() oder mysqli_init() zurückgegebenes Verbindungsobjekt.

query

The query, as a string.

Hinweis:
You should not add a terminating semicolon or \g to the statement.

This parameter can include one or more parameter markers in the SQL statement by embedding question mark (?) characters at the appropriate positions.

Hinweis:
The markers are legal only in certain places in SQL statements. For example, they are allowed in the VALUES() list of an INSERT statement (to specify column values for a row), or in a comparison with a column in a WHERE clause to specify a comparison value.

However, they are not allowed for identifiers (such as table or column names), in the select list that names the columns to be returned by a SELECT statement, or to specify both operands of a binary operator such as the = equal sign. The latter restriction is necessary because it would be impossible to determine the parameter type. It's not allowed to compare marker with NULL by ? IS NULL too. In general, parameters are legal only in Data Manipulation Language (DML) statements, and not in Data Definition Language (DDL) statements.

Rückgabewerte

mysqli_prepare() returns a statement object or FALSE if an error occurred.

Beispiele

Beispiel #1 mysqli::prepare() example

Objektorientierter Stil


<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}

$city = "Amersfoort";

/* create a prepared statement */
if ($stmt = $mysqli->prepare("SELECT District FROM City WHERE Name=?")) {

    /* bind parameters for markers */
    $stmt->bind_param("s", $city);

    /* execute query */
    $stmt->execute();

    /* bind result variables */
    $stmt->bind_result($district);

    /* fetch value */
    $stmt->fetch();

    printf("%s is in district %s\n", $city, $district);

    /* close statement */
    $stmt->close();
}

/* close connection */
$mysqli->close();
?>

Prozeduraler Stil


<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}

$city = "Amersfoort";

/* create a prepared statement */
if ($stmt = mysqli_prepare($link, "SELECT District FROM City WHERE Name=?")) {

    /* bind parameters for markers */
    mysqli_stmt_bind_param($stmt, "s", $city);

    /* execute query */
    mysqli_stmt_execute($stmt);

    /* bind result variables */
    mysqli_stmt_bind_result($stmt, $district);

    /* fetch value */
    mysqli_stmt_fetch($stmt);

    printf("%s is in district %s\n", $city, $district);

    /* close statement */
    mysqli_stmt_close($stmt);
}

/* close connection */
mysqli_close($link);
?>

Die obigen Bespiele erzeugen folgende Ausgabe:

Amersfoort is in district Utrecht

Siehe auch

mysqli_stmt_execute() - Executes a prepared Query
mysqli_stmt_fetch() - Fetch results from a prepared statement into the bound variables
mysqli_stmt_bind_param() - Binds variables to a prepared statement as parameters
mysqli_stmt_bind_result() - Binds variables to a prepared statement for result storage
mysqli_stmt_close() - Closes a prepared statement