mysqli_stmt::data_seek

mysqli_stmt_data_seek

(PHP 5, PHP 7)

mysqli_stmt::data_seek -- mysqli_stmt_data_seek — Seeks to an arbitrary row in statement result set

说明

面向对象风格

mysqli_stmt::data_seek ( int $offset ) : void

过程化风格

mysqli_stmt_data_seek ( mysqli_stmt $stmt , int $offset ) : void

Seeks to an arbitrary result pointer in the statement result set.

mysqli_stmt_store_result() must be called prior to mysqli_stmt_data_seek().

参数

stmt

仅以过程化样式：由 mysqli_stmt_init() 返回的 statement 标识。

offset

Must be between zero and the total number of rows minus one (0.. mysqli_stmt_num_rows() - 1).

返回值

没有返回值。

范例

Example #1 面向对象风格

<?php
/* Open a connection */
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");

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

$query = "SELECT Name, CountryCode FROM City ORDER BY Name";
if ($stmt = $mysqli->prepare($query)) {

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

    /* bind result variables */
    $stmt->bind_result($name, $code);

    /* store result */
    $stmt->store_result();

    /* seek to row no. 400 */
    $stmt->data_seek(399);

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

    printf ("City: %s  Countrycode: %s\n", $name, $code);

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

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

Example #2 过程化风格

<?php
/* Open a connection */
$link = mysqli_connect("localhost", "my_user", "my_password", "world");

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

$query = "SELECT Name, CountryCode FROM City ORDER BY Name";
if ($stmt = mysqli_prepare($link, $query)) {

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

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

    /* store result */
    mysqli_stmt_store_result($stmt);

    /* seek to row no. 400 */
    mysqli_stmt_data_seek($stmt, 399);

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

    printf ("City: %s  Countrycode: %s\n", $name, $code);

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

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

以上例程会输出：

City: Benin City  Countrycode: NGA

参见

User Contributed Notes

phpnet at stuffonmylaptop dot com 23-Nov-2011 03:25
Although the documentation says you must provide a number between 0 and count - 1, you can actually supply a negative number, which appears to be cast to positive (such as in abs()).

For example:

<?php
$db = new mysqli('localhost', 'test', 'password', 'schema');
$db->multi_query("
            SELECT * FROM
            (
                SELECT 1 as 'position'
                UNION SELECT 2 as 'position'
                UNION SELECT 3 as 'position'
                UNION SELECT 4 as 'position'
                UNION SELECT 5 as 'position'
            ) as rows");
           
$result = $db->store_result();

for ($i = 0; $i < $result->num_rows; $i++)
{
    $offset = $i;
    $result->data_seek($offset);
    var_dump("Seek offset is: {$offset}", $result->fetch_object());
}

for ($i = 0; $i < $result->num_rows; $i++)
{
    $offset = -$i;
    $result->data_seek($offset);
    var_dump("Seek offset is: {$offset}", $result->fetch_object());
}