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mysqli::query

MySQLi PHP Manual

(PHP 5)

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

Beschreibung

Object oriented style (method):

mixed mysqli::query ( string $query [, int $resultmode ] )

Procedural style:

mixed mysqli_query ( mysqli $link , string $query [, int $resultmode ] )

Performs a query against the database.

Functionally, using this function is identical to calling mysqli_real_query() followed either by mysqli_use_result() or mysqli_store_result().

Parameter-Liste

link

Nur bei prozeduralem Aufruf: Ein von mysqli_connect() oder mysqli_init() zurückgegebenes Verbindungsobjekt.

query

The query string.

Data inside the query should be properly escaped.

resultmode

Either the constant MYSQLI_USE_RESULT or MYSQLI_STORE_RESULT depending on the desired behavior. By default, MYSQLI_STORE_RESULT is used.

If you use MYSQLI_USE_RESULT all subsequent calls will return error Commands out of sync unless you call mysqli_free_result()

With MYSQLI_ASYNC (available with mysqlnd), it is possible to perform query asynchronously. mysqli_poll() is then used to get results from such queries.

Rückgabewerte

Gibt bei Erfolg TRUE zurück. Im Fehlerfall wird FALSE zurückgegeben. For SELECT, SHOW, DESCRIBE or EXPLAIN mysqli_query() will return a result object.

Changelog

Version Beschreibung
5.3.0 Added the ability of async queries.

Beispiele

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$mysqli = new mysqli("localhost", "my_user", "my_password", "world"); /* check connection */ if (mysqli_connect_errno()) { printf("Connect failed: %s\n", mysqli_connect_error()); exit(); } /* Create table doesn't return a resultset */ if ($mysqli->query("CREATE TEMPORARY TABLE myCity LIKE City") === TRUE) { printf("Table myCity successfully created.\n"); } /* Select queries return a resultset */ if ($result = $mysqli->query("SELECT Name FROM City LIMIT 10")) { printf("Select returned %d rows.\n", $result->num_rows); /* free result set */ $result->close(); } /* If we have to retrieve large amount of data we use MYSQLI_USE_RESULT */ if ($result = $mysqli->query("SELECT * FROM City", MYSQLI_USE_RESULT)) { /* Note, that we can't execute any functions which interact with the server until result set was closed. All calls will return an 'out of sync' error */ if (!$mysqli->query("SET @a:='this will not work'")) { printf("Error: %s\n", $mysqli->error); } $result->close(); } $mysqli->close();

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$link = mysqli_connect("localhost", "my_user", "my_password", "world"); /* check connection */ if (mysqli_connect_errno()) { printf("Connect failed: %s\n", mysqli_connect_error()); exit(); } /* Create table doesn't return a resultset */ if (mysqli_query($link, "CREATE TEMPORARY TABLE myCity LIKE City") === TRUE) { printf("Table myCity successfully created.\n"); } /* Select queries return a resultset */ if ($result = mysqli_query($link, "SELECT Name FROM City LIMIT 10")) { printf("Select returned %d rows.\n", mysqli_num_rows($result)); /* free result set */ mysqli_free_result($result); } /* If we have to retrieve large amount of data we use MYSQLI_USE_RESULT */ if ($result = mysqli_query($link, "SELECT * FROM City", MYSQLI_USE_RESULT)) { /* Note, that we can't execute any functions which interact with the server until result set was closed. All calls will return an 'out of sync' error */ if (!mysqli_query($link, "SET @a:='this will not work'")) { printf("Error: %s\n", mysqli_error($link)); } mysqli_free_result($result); } mysqli_close($link);

Das oben gezeigte Beispiel erzeugt folgende Ausgabe:

Table myCity successfully created.
Select returned 10 rows.
Error: Commands out of sync;  You can't run this command now

Siehe auch

MySQLi PHP Manual