PHP Manual
mysqli
Performs a query on the database

mysqli::query

mysqli_query

(PHP 5, PHP 7, PHP 8)

mysqli::query -- mysqli_query — Performs a query on the database

Beschreibung

Objektorientierter Stil

public mysqli::query(string $query, int $result_mode = MYSQLI_STORE_RESULT): mysqli_result|bool

Prozeduraler Stil

mysqli_query(mysqli $mysql, string $query, int $result_mode = MYSQLI_STORE_RESULT): mysqli_result|bool

Performs a query against the database.

For non-DML queries (not INSERT, UPDATE or DELETE), this function is similar to calling mysqli_real_query() followed by either mysqli_use_result() or mysqli_store_result().

Hinweis:
In the case where you pass a statement to mysqli_query() 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.

Parameter-Liste

mysql

Nur bei prozeduralem Aufruf: Ein von mysqli_connect() oder mysqli_init() zurückgegebenes mysqli-Objekt.

query

The query string.

Warnung

Sicherheitswarnung: SQL-Injection

Wenn die Abfrage irgendwelche Eingabevariablen enthält, sollten stattdessen parametrisierte Prepared Statements verwendet werden. Alternativ dazu müssen die Daten korrekt formatiert sein und alle Strings müssen mit der Funktion mysqli_real_escape_string() maskiert werden.

result_mode

The result mode can be one of 3 constants indicating how the result will be returned from the MySQL server.

MYSQLI_STORE_RESULT (default) - returns a mysqli_result object with buffered result set.

MYSQLI_USE_RESULT - returns a mysqli_result object with unbuffered result set. As long as there are pending records waiting to be fetched, the connection line will be busy and all subsequent calls will return error Commands out of sync. To avoid the error all records must be fetched from the server or the result set must be discarded by calling mysqli_free_result().

MYSQLI_ASYNC (available with mysqlnd) - the query is performed asynchronously and no result set is immediately returned. mysqli_poll() is then used to get results from such queries. Used in combination with either MYSQLI_STORE_RESULT or MYSQLI_USE_RESULT constant.

Rückgabewerte

Returns false on failure. For successful queries which produce a result set, such as SELECT, SHOW, DESCRIBE or EXPLAIN, mysqli_query() will return a mysqli_result object. For other successful queries, mysqli_query() will return true.

Beispiele

Beispiel #1 mysqli::query() example

Objektorientierter Stil


<?php

mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");

/* Create table doesn't return a resultset */
$mysqli->query("CREATE TEMPORARY TABLE myCity LIKE City");
printf("Table myCity successfully created.\n");

/* Select queries return a resultset */
$result = $mysqli->query("SELECT Name FROM City LIMIT 10");
printf("Select returned %d rows.\n", $result->num_rows);

/* If we have to retrieve large amount of data we use MYSQLI_USE_RESULT */
$result = $mysqli->query("SELECT * FROM City", MYSQLI_USE_RESULT);

/* Note, that we can't execute any functions which interact with the
    server until all records have been fully retrieved or the result
    set was closed. All calls will return an 'out of sync' error */
$mysqli->query("SET @a:='this will not work'");

Prozeduraler Stil


<?php

mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$link = mysqli_connect("localhost", "my_user", "my_password", "world");

/* Create table doesn't return a resultset */
mysqli_query($link, "CREATE TEMPORARY TABLE myCity LIKE City");
printf("Table myCity successfully created.\n");

/* Select queries return a resultset */
$result = mysqli_query($link, "SELECT Name FROM City LIMIT 10");
printf("Select returned %d rows.\n", mysqli_num_rows($result));

/* If we have to retrieve large amount of data we use MYSQLI_USE_RESULT */
$result = mysqli_query($link, "SELECT * FROM City", MYSQLI_USE_RESULT);

/* Note, that we can't execute any functions which interact with the
    server until all records have been fully retrieved or the result
    set was closed. All calls will return an 'out of sync' error */
mysqli_query($link, "SET @a:='this will not work'");

Die oben gezeigten Beispiele erzeugen eine ähnliche Ausgabe wie:

Table myCity successfully created.
Select returned 10 rows.

Fatal error: Uncaught mysqli_sql_exception: Commands out of sync; you can't run this command now in...