Introduction
In this article I describe the PHP MySQLi functions mysqli_fetch_fields, mysqli_fetch_lengths, mysqli_fetch_object, mysqli_fetch_row and mysqli-field_count. To learn some other MySQLi functions, go to:
- MySQLi Function in PHP: Part 1
- MySQLi Function in PHP: Part 2
- MySQLi Function in PHP: Part 3
- MySQLi Function in PHP: Part 4
PHP mysqli_fetch_fields() Function
The PHP MySQLi "mysqli_fetch_fields" function returns an array of objects representing the fields in a result set or you can say that this function returns an array of objects that contains information or returns false if no field information is available.
Syntax
mysqli_fetch_fields(result, resulttype) |
Parameter in mysqli_fetch_fields function
The parameter of the function is:
Parameter |
Description |
result |
It specifies a result set identifier returned by mysqli_query(), mysqli_store_result() or mysqli_user_result(). |
Example
An example of the function is:
<?php
$con=mysqli_connect("localhost","root","","mysql");
if (mysqli_connect_errno($con))
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
if($result=mysqli_query($con,"SELECT * FROM emp"))
{
$fieldsinfo=mysqli_fetch_fields($result);
foreach ($fieldsinfo as $val)
{
printf("<b>Name:</b> %s",$val->name);
printf(" <b>Table:</b> %s",$val->table);
printf(" <b>max. Len:</b> %d",$val->max_length);
echo "</br>";
}
}
mysqli_close($con);
?>
Output
PHP mysqli_fetch_lengths() Function
The PHP MySQLi "mysqli_fetch_lengths function" gets the length of each output in a result and this function returns an array of lengths on success or false on failure.
Syntax
mysqli_fetch_lengths(result, resulttype) |
Parameter in mysqli_fetch_lengths function
The parameter of the function is:
Parameter |
Description |
result |
It specifies a result set identifier returned by mysqli_query(), mysqli_store_result() or mysqli_user_result(). |
Example
An example of the function is:
<?php
$con=mysqli_connect("localhost","root","","mysql");
if (mysqli_connect_errno($con))
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$qry=mysqli_query($con,"SELECT * FROM emp");
$row=mysqli_fetch_assoc($qry);
$lengths=mysqli_fetch_lengths($qry);
echo "<pre>";
print_r($row);
echo "<pre>";
echo "</br>";
print_r($lengths);
mysqli_close($con);
?>
Output
PHP mysqli_fetch_object() Function
The PHP MySQLi "mysqli_fetch_objects" function returns the current row of a result set as an object or in other words this function returns an object with string properties that corresponds to the fetched row or null if there are no more rows in the result set.
Syntax
mysqli_fetch_object(result,classname,params) |
Parameter in mysqli_fetch_object function
The parameters of the function are:
Parameter |
Description |
result |
It specifies a result set identifier returned by mysqli_query(), mysqli_store_result() or mysqli_user_result(). |
classname |
It specifies the name of the class to instantiate and return. If not specified a class object is returned. |
params |
It specifies an array of parameters to pass to the constructor for classname objects. |
Example
An example of the function is:
<?php
$con=mysqli_connect("localhost","root","","mysql");
if (mysqli_connect_errno($con))
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
echo "<table border='1'>
<tr>
<th>EmpId</th>
<th>EmpName</th>
</tr>";
if($qry=mysqli_query($con,"SELECT * FROM emp"))
{
while($res=mysqli_fetch_object($qry))
{
echo "<tr>";
echo "<td>" . $res->id . "</td>";
echo "<td>" . $res->name . "</td>";
echo "</tr>";
}
}
echo "</table>";
mysqli_close($con);
?>
Output
PHP mysqli_fetch_row() Function
The PHP MySQLi "mysqli_fetch_lengths" function gets a result row as an enumerated array and this function returns an array of strings that corresponds to the fetched row or null if there are no more rows in the result set.
Syntax
Parameter in mysqli_fetch_row function
The parameter of the function is:
Parameter |
Description |
result |
It specifies a result set identifier returned by mysqli_query(), mysqli_store_result() or mysqli_user_result(). |
Example
An example of the function is:
<?php
$con=mysqli_connect("localhost","root","","mysql");
if (mysqli_connect_errno($con))
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
echo "<table border='1'>
<tr>
<th>EmpId</th>
<th>EmpName</th>
<th>EmpSalary</th>
</tr>";
if($qry=mysqli_query($con,"SELECT * FROM emp"))
{
while($res=mysqli_fetch_row($qry))
{
echo "<tr>";
echo "<td>" . $res[0] . "</td>";
echo "<td>" . $res[1] . "</td>";
echo "<td>" . $res[2] . "</td>";
echo "</tr>";
}
}
echo "</table>";
mysqli_close($con);
?>
Output
PHP mysqli_field_count() Function
The PHP MySQLi "mysqli_field_count" function returns the number of columns for the most recent query and this function returns an integer representing the number of fields in a result set.
Syntax
mysqli_field_count(connection) |
Parameter in mysqli_field_count function
The parameter of the function is:
Parameter |
Description |
connection |
It specifies the MySQL connection to use. |
Example
An example of the function is:
<?php
$con=mysqli_connect("localhost","root","","mysql");
if (mysqli_connect_errno($con))
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
mysqli_query($con,"SELECT * FROM emp");
echo "Total no of fields is: ".mysqli_field_count($con);
mysqli_close($con);
?>
Output