mysqli::query

mysqli_query

(PHP 5)

mysqli_query — Performs a query on the database

Description

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().

Parameters

link

Procedural style only: A link identifier returned by mysqli_connect() or mysqli_init()

query

The query string.

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()

Return Values

Returns TRUE on success or FALSE on failure. For SELECT, SHOW, DESCRIBE or EXPLAIN mysqli_query() will return a result object.

Examples

Example #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();

?>

Example #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);

?>

The above example will output:

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