mysqli_stmt::result_metadata

mysqli_stmt_result_metadata

(PHP 5, PHP 7, PHP 8)

mysqli_stmt::result_metadata -- mysqli_stmt_result_metadata — Returns result set metadata from a prepared statement

Açıklama

Nesne yönelimli kullanım

public mysqli_stmt::result_metadata(): mysqli_result|false

Yordamsal kullanım

mysqli_stmt_result_metadata(mysqli_stmt $statement): mysqli_result|false

If a statement passed to mysqli_prepare() is one that produces a result set, mysqli_stmt_result_metadata() returns the result object that can be used to process the meta information such as total number of fields and individual field information.

This function returns an empty mysqli_result object which can be used to access metadata information from the prepared statement without having to fetch the actual rows of data. There is no need to use this function when using mysqli_stmt_get_result() to retrieve the entire result set from a prepared statement as a result object.

Bilginize:
This result set object can be passed as an argument only to the field-based functions that process result set metadata, such as:

mysqli_num_fields()

mysqli_fetch_field()

mysqli_fetch_field_direct()

mysqli_fetch_fields()

mysqli_field_count()

mysqli_field_seek()

mysqli_field_tell()

mysqli_free_result()

Bilginize: The result set returned by mysqli_stmt_result_metadata() contains only metadata. It does not contain any row results. The rows are obtained by calling mysqli_stmt_get_result() on the statement handle or with mysqli_stmt_fetch().

Bağımsız Değişkenler

deyim: Sadece yordamsal tarz: mysqli_stmt_init() işlevinden dönen bir mysqli_stmt nesnesi.

Dönen Değerler

Returns a result object or false if an error occurred. If the statement does not produce a result set, false is returned as well.

Hatalar/İstisnalar

Eğer mysqli hata bildirimi etkinse (MYSQLI_REPORT_ERROR) ve istenen işlem başarısız olursa bir uyarı üretilir. Ek olarak, kip MYSQLI_REPORT_STRICT ise bunun yerine mysqli_sql_exception istisnası oluşur.

Örnekler

Örnek 1 Nesne yönelimli kullanım

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

$mysqli->query("DROP TABLE IF EXISTS friends");
$mysqli->query("CREATE TABLE friends (id int, name varchar(20))");

$mysqli->query("INSERT INTO friends VALUES (1,'Hartmut'), (2, 'Ulf')");

$stmt = $mysqli->prepare("SELECT id, name FROM friends");
$stmt->execute();

/* get resultset for metadata */
$result = $stmt->result_metadata();

/* retrieve field information from metadata result set */
$field = $result->fetch_field();

printf("Fieldname: %s\n", $field->name);
?>

Örnek 2 Yordamsal kullanım

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

mysqli_query($link, "DROP TABLE IF EXISTS friends");
mysqli_query($link, "CREATE TABLE friends (id int, name varchar(20))");

mysqli_query($link, "INSERT INTO friends VALUES (1,'Hartmut'), (2, 'Ulf')");

$stmt = mysqli_prepare($link, "SELECT id, name FROM friends");
mysqli_stmt_execute($stmt);

/* get resultset for metadata */
$result = mysqli_stmt_result_metadata($stmt);

/* retrieve field information from metadata result set */
$field = mysqli_fetch_field($result);

printf("Fieldname: %s\n", $field->name);
?>

Ayrıca Bakınız

mysqli_prepare() - Prepares an SQL statement for execution
mysqli_free_result() - Frees the memory associated with a result
mysqli_stmt_get_result() - Gets a result set from a prepared statement as a mysqli_result object