7.3.9.23 mysqli_stmt::prepare, mysqli_stmt_prepare

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• mysqli_stmt::prepare

  mysqli_stmt_prepare

  Prepare an SQL statement for execution

Description

Object oriented style

public mixed mysqli_stmt::prepare(string query);

Procedural style

bool mysqli_stmt_prepare(mysqli_stmt stmt,
                         string query);

Prepares the SQL query pointed to by the null-terminated string query.

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.

Note

In the case where you pass a statement to mysqli_stmt_prepare that is longer than max_allowed_packet of the server, the returned error codes are different depending on whether you are using MySQL Native Driver (mysqlnd) or MySQL Client Library (libmysqlclient). The behavior is as follows:

• mysqlnd on Linux returns an error code of 1153. The error message means “got a packet bigger than max_allowed_packet bytes”.

• mysqlnd on Windows returns an error code 2006. This error message means “server has gone away”.

• libmysqlclient on all platforms returns an error code 2006. This error message means “server has gone away”.

Parameters

stmt

Procedural style only: A statement identifier returned by mysqli_stmt_init.

query

The query, as a string. It must consist of a single SQL statement.

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

Note

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

Note

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. In general, parameters are legal only in Data Manipulation Language (DML) statements, and not in Data Definition Language (DDL) statements.

Return Values

Returns true on success or false on failure.

Examples

Example 7.103 Object oriented style

<?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 */
$stmt =  $mysqli->stmt_init();
if ($stmt->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();
?>

Example 7.104 Procedural style

<?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 */
$stmt = mysqli_stmt_init($link);
if (mysqli_stmt_prepare($stmt, 'SELECT District FROM City WHERE Name=?')) {
    /* bind parameters for markers */
    mysqli_stmt_bind_param($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);
?>

The above examples will output:

Amersfoort is in district Utrecht

See Also

mysqli_stmt_init

mysqli_stmt_execute

mysqli_stmt_fetch

mysqli_stmt_bind_param

mysqli_stmt_bind_result

mysqli_stmt_get_result

mysqli_stmt_close