(PHP 5)
mysqli_stmt::data_seek -- mysqli_stmt_data_seek — Seeks to an arbitrary row in statement result set
面向对象风格
$offset
)过程化风格
Seeks to an arbitrary result pointer in the statement result set.
mysqli_stmt_store_result() must be called prior to mysqli_stmt_data_seek().
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).
没有返回值。
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
phpnet at stuffonmylaptop dot com (2011-11-23 15:25:40)
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());
}
john at innercurmudgeon dot com (2008-01-07 22:13:51)
mysqli_stmt_data_seek() only works if you have previously called mysqli_stmt_store_result().