Performs a query on the database (original) (raw)
mysqli::query
mysqli_query
(PHP 5, PHP 7)
mysqli::query -- mysqli_query — Performs a query on the database
Description
Object oriented style
public mysqli::query ( string $query
[, int $resultmode
= MYSQLI_STORE_RESULT ] ) : mixed
mysqli_query ( mysqli $link
, string $query
[, int $resultmode
= MYSQLI_STORE_RESULT ] ) : mixed
For non-DML queries (not INSERT, UPDATE or DELETE), this function is similar to calling mysqli_real_query() followed by eithermysqli_use_result() or mysqli_store_result().
Note:
In the case where you pass a statement tomysqli_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 thanmax_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.
Parameters
link
Procedural style only: A link identifier returned by mysqli_connect() or mysqli_init()
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.
Return Values
Returns FALSE
on failure. For successful SELECT, SHOW, DESCRIBE
orEXPLAIN
queries mysqli_query() will return a mysqli_result object. For other successful queries mysqli_query() will return TRUE
.
Changelog
Version | Description |
---|---|
5.3.0 | Added the ability of async queries. |
Examples
Example #1 mysqli::query() example
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(); ?>
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); ?>
The above examples will output:
Table myCity successfully created. Select returned 10 rows. Error: Commands out of sync; You can't run this command now
See Also
- mysqli_real_query() - Execute an SQL query
- mysqli_multi_query() - Performs a query on the database
- mysqli_free_result() - Frees the memory associated with a result