The WHERE clause
The WHERE clause is used to extract only those records that fulfill a specified criterion.
Syntax
SELECT column_name(s)
FROM table_name
WHERE column_name operator value
FROM table_name
WHERE column_name operator value
To get PHP to execute the statement above we must use the mysqli_query() function. This function is used to send a query or command to a MySQL connection.
Example
The following example selects all rows from the “Persons” table where “FirstName=’Peter'”:
<?php
$con=mysqli_connect(“example.com”,”peter”,”abc123″,”my_db”);
// Check connection
if (mysqli_connect_errno())
{
echo “Failed to connect to MySQL: ” . mysqli_connect_error();
}
$con=mysqli_connect(“example.com”,”peter”,”abc123″,”my_db”);
// Check connection
if (mysqli_connect_errno())
{
echo “Failed to connect to MySQL: ” . mysqli_connect_error();
}
$result = mysqli_query($con,”SELECT * FROM Persons
WHERE FirstName=’Peter'”);
while($row = mysqli_fetch_array($result))
{
echo $row[‘FirstName’] . ” ” . $row[‘LastName’];
echo “<br>”;
}
?>
