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<mysqli_prepare mysqli_real_connect>
Letzte Aktualisierung: Thu, 21 Aug 2014
 

mysqli_query

(PHP 5)

mysqli_query

(no version information, might be only in CVS)

mysqli->query -- Performs a query on the database

Description

Procedural style:

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

Object oriented style (method):

class mysqli {

mixed query ( string query [, int resultmode] )

}

The mysqli_query() function is used to simplify the act of performing a query against the database represented by the link parameter.

Functionally, using this function is identical to calling mysqli_real_query() followed either by mysqli_use_result() or mysqli_store_result() where query is the query string itself and resultmode is either the constant MYSQLI_USE_RESULT or MYSQLI_STORE_RESULT depending on the desired behavior. By default, if the resultmode is not provided MYSQLI_STORE_RESULT is used.

If you execute mysqli_query() with resultmode MYSQLI_USE_RESULT all subsequent calls will return error Commands out of sync unless you call mysqli_free_result().

Rückgabewerte

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

Beispiele

Beispiel 1. Object oriented style

<?php
$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();
?>

Beispiel 2. Procedural style

<?php
$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


<mysqli_prepare mysqli_real_connect>
Letzte Aktualisierung: Thu, 21 Aug 2014
 


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