SQL WHERE Clause.
A SQL WHERE clause filters for rows to a particular criteria.
WHERE clause can be limited from the expression.
WHERE by condition that returns either true or false.
WHERE is used with SELECT, UPDATE, and DELETE.
SELECT column_name,column_name
FROM table_name
WHERE column_name operator value;
Selecting the column name from the table where column name is equal to some value.
Let's learn.StudentID | StudentName | ParentsContact | Address | Country | DOB | Section |
1 |
Liam | 10101010 | 23 MG road Banglore |
INDIA | 12/06 | A |
2 | Andrew | 20202020 | 2415 Anthony market str | Germany | 01/02 | A |
3 | Joshua | 30303030 | 26547 David church road | USA | 18/04 | B |
4 | Ryan | 40404040 | 18 Krishna sq. Banglore |
INDIA | 26/12 | B |
5 | Charles | 50505050 | 878 Eli Berguvsvägen 8 | INDIA | 23/11 | C |
SELECT * FROM student WHERE DOB='18/04'"
3.Create index.php and implement code in PHP script .
$sql = "SELECT * FROM student WHERE DOB='18/04'";
..
if($data = mysqli_query($connect, $sql)){
if(mysqli_num_rows($asc) > 0){
...
}
}
Operator Description
= Equal
<> Not equal.we can also written as !=
> Greater than
< Less than
>= Greater than or equal
<= Less than or equal
BETWEEN Between an inclusive range
LIKE Search for a pattern
IN To specify multiple possible values for a column
<!DOCTYPE html>
<html lang="en">
<head>
<title>How can i use SQL WHERE Clause</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css">
</head>
<body>
<div class="container">
<br>
<br>
<br>
<div class="text-center">
<h1>SQL WHERE Clause</h1>
</div>
<div class="well">
<?php
$connect = mysqli_connect("localhost", "root", "", "school_management");
if ($connect->connect_error) {
die("Connection failed: " . $connect->connect_error);
}
$sql = "SELECT * FROM student WHERE DOB='18/04'";
if($asc = mysqli_query($connect, $sql)){
if(mysqli_num_rows($asc) > 0){
echo "<table class='table'>
<tr>
<th>StudentName</th>
<th>DOB</th>
</tr>
";
while($row = $asc->fetch_assoc()){
echo "<tr>
<td>" . $row['StudentName'] . "</td>";
echo "<td>".$row['DOB']."</td>
</tr>";
}
echo "</table>";
} else{
echo "No records found.";
}
}
?>
</div>
<br>
</div>
</body>
</html>