mysqli_query

Performs a query on the database (PHP 5)
mixed mysqli_query ( mysqli link, string query [, int resultmode] )

Procedural style:

Object oriented style (method):

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().

返回值

如果成功则返回 TRUE,失败则返回 FALSE。 For SELECT, SHOW, DESCRIBE or EXPLAIN mysqli_query() will return a result object.

范例

例 1315. 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();
?>

例 1316. 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);
?>

上例将输出:

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