PHP mysqli: use_result() function
mysqli_use_result function / mysqli::use_result
The mysqli_use_result function / mysqli::use_result — initiate a result set retrieval.
Syntax:
Object oriented style
mysqli_result mysqli::use_result ( void )
Procedural style
mysqli_result mysqli_use_result ( mysqli $link )
Parameter:
Name | Description | Required/Optional | |
---|---|---|---|
link | A link identifier returned by mysqli_connect() or mysqli_init() | Required for procedural style only and Optional for Object oriented style |
Usage: Procedural style
mysqli_use_result(connection);
Parameter:
Name | Description | Required/Optional |
---|---|---|
connection | Specifies the MySQL connection to use. | Required |
Return value:
Returns an unbuffered result object or FALSE if an error occurred.
Version: PHP 5, PHP 7
Example of object oriented style:
<?php
$mysqli = new mysqli("localhost", "my_user", "datasoft123", "hr");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
$query = "SELECT CURRENT_USER();";
$query .= "SELECT Name FROM City ORDER BY ID LIMIT 20, 5";
/* execute multi query */
if ($mysqli->multi_query($query)) {
do {
/* store first result set */
if ($result = $mysqli->use_result()) {
while ($row = $result->fetch_row()) {
printf("%s\n", $row[0]);
}
$result->close();
}
/* print divider */
if ($mysqli->more_results()) {
printf("-----------------\n");
}
} while ($mysqli->next_result());
}
/* close connection */
$mysqli->close();
?>
Output:
[email protected]% -----------------
Example of the Procedural style
<?php
$link = mysqli_connect("localhost", "user", "datasoft123", "hr");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
$query = "SELECT CURRENT_USER();";
$query .= "SELECT Name FROM city ORDER BY ID LIMIT 20, 5";
/* execute multi query */
if (mysqli_multi_query($link, $query)) {
do {
/* store first result set */
if ($result = mysqli_use_result($link)) {
while ($row = mysqli_fetch_row($result)) {
printf("%s\n", $row[0]);
}
mysqli_free_result($result);
}
/* print divider */
if (mysqli_more_results($link)) {
printf("-----------------\n");
}
} while (mysqli_next_result($link));
}
/* close connection */
mysqli_close($link);
?>
Output:
Connect failed: Access denied for user 'user'@'localhost' (using password: YES)
Example:
<?php
$con=mysqli_connect("localhost","user1","datasoft123","hr");
//* The connection failed */
if (mysqli_connect_errno()) {
printf("The connection failed: %s\n", mysqli_connect_error());
exit();
}
$sql = "SELECT CURRENT_USER();";
$sql .= "SELECT Name FROM City ORDER BY ID LIMIT 20, 5";
/* run a multi with */
if ($con->multi_query($sql)) {
do {
/* first store the result set */
if ($resultado = $con->use_result()) {
while ($fila = $resultado->fetch_row()) {
printf("%s\n", $fila[0]);
}
$resultado->close();
}
/* print a separator */
if ($con->more_results()) {
printf("-----------------\n");
}
} while ($con->next_result());
}
// close connections
$con->close();
?>
Sample Output:
[email protected]% -----------------
See also
Previous: thread_safe
Next: warning_count
PHP: Tips of the Day
Getting all defined constants
To get all defined constants including those created by PHP use the get_defined_constants function:
Example:
<?php $constants = get_defined_constants(); var_dump($constants); // pretty large list
Output:
array(2250) { ["E_ERROR"]=> int(1) ["E_RECOVERABLE_ERROR"]=> int(4096) ["E_WARNING"]=> ..... ..... resource(1) of type (stream) ["STDOUT"]=> resource(2) of type (stream) ["STDERR"]=> resource(3) of type (stream) }
To get only those constants that were defined by your app call the function at the beginning and at the end of your script (normally after the bootstrap process):
<?php $constants = get_defined_constants(); define("HELLO", "hello"); define("WORLD", "world"); $new_constants = get_defined_constants(); $myconstants = array_diff_assoc($new_constants, $constants); var_export($myconstants);
Output:
array ( 'HELLO' => 'hello', 'WORLD' => 'world', )
It's sometimes useful for debugging
- Weekly Trends
- Java Basic Programming Exercises
- SQL Subqueries
- Adventureworks Database Exercises
- C# Sharp Basic Exercises
- SQL COUNT() with distinct
- JavaScript String Exercises
- JavaScript HTML Form Validation
- Java Collection Exercises
- SQL COUNT() function
- SQL Inner Join
- JavaScript functions Exercises
- Python Tutorial
- Python Array Exercises
- SQL Cross Join
- C# Sharp Array Exercises
We are closing our Disqus commenting system for some maintenanace issues. You may write to us at reach[at]yahoo[dot]com or visit us at Facebook