mysqli_stmt::result_metadata

mysqli_stmt_result_metadata

Returns result set metadata from a prepared statement

Beschreibung

Objektorientierter Stil

mysqli_result mysqli_stmt::result_metadata ( void )

Prozeduraler Stil

mysqli_result mysqli_stmt_result_metadata ( mysqli_stmt $stmt )

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.

Hinweis:
This result set pointer can be passed as an argument to any of 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

The result set structure should be freed when you are done with it, which you can do by passing it to mysqli_free_result

Hinweis:
The result set returned by mysqli_stmt_result_metadata contains only metadata. It does not contain any row results. The rows are obtained by using the statement handle with mysqli_stmt_fetch.

Parameter-Liste

stmt: Nur bei prozeduralem Aufruf: ein von mysqli_stmt_init zurückgegebenes Statementobjekt.

Rückgabewerte

Returns a result object or FALSE if an error occurred.

Beispiele

Beispiel #1 Objektorientierter Stil


<?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);

/* close resultset */
$result->close();

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

Beispiel #2 Prozeduraler Stil


<?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);

/* close resultset */
mysqli_free_result($result);

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

Siehe auch

mysqli_prepare
mysqli_free_result