PHP MySQL WHERE sharti
MySQL ma’lumotlar bazasidan ma’lumotlarni tanlang va filtrlang
SQL WHERE bandi yozuvlarni filtrlash uchun ishlatiladi.
WHERE bandi faqat belgilangan shartni bajaradigan yozuvlarni chiqarish uchun ishlatiladi.
SELECT column_name(s) FROM table_name WHERE column_name operator value
SQL haqida ko‘proq ma’lumot olish uchun bizning SQL qo‘llanmamizga tashrif buyuring.
MySQLi yordamida ma’lumotlarni tanlang va filtrlang
Quyidagi misol MyGuests jadvalidan identifikator, ism va familiya ustunlarini tanlaydi, bu yerda familiya "Doe" bo‘ladi va uni sahifada ko‘rsatadi:
Misol - MySQLi obyektga yo‘naltirilgan
<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";
// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$sql = "SELECT id, firstname, lastname FROM MyGuests WHERE lastname='Doe'";
// Execute the SQL query
$result = $conn->query($sql);
// Process the result set
if ($result->num_rows > 0) {
// Output data of each row
while($row = $result->fetch_assoc()) {
echo "id: " . $row["id"]. " - Name: " . $row["firstname"]. " " . $row["lastname"]. "<br>";
}
} else {
echo "0 results";
}
$conn->close();
?>
Misolni ishga tushirish »
Kod tushuntirish
Birinchidan, familiyasi "Doe" bo‘lgan MyGuests jadvalidan id, ism va familiya ustunlarini tanlaydigan SQL so‘rovini o‘rnatamiz.
Keyingi kod satri $conn->query($sql) so‘rovni ishga tushiradi va olingan ma’lumotlarni $result deb nomlangan o‘zgaruvchiga joylashtiradi.
Keyin $result->num_rows>0 qatori qaytarilgan 0 dan ortiq qator mavjudligini tekshiradi.
Agar 0 dan ortiq satr qaytarilsa, fetch_assoc() funksiyasi natijalar to‘plamini biz aylanib o‘tishimiz mumkin bo‘lgan assotsiativ massivga joylashtiradi. while() sikli natijalar to‘plami bo‘ylab o‘tadi va id, firstname va lastname ustunlaridan ma’lumotlarni chiqaradi.
Quyidagi misol MySQLi-da yuqoridagi misol bilan bir xil narsani ko‘rsatadi protsessual metod:
Misol - MySQLi protsessual
<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";
// Create connection
$conn = mysqli_connect($servername, $username, $password, $dbname);
// Check connection
if (!$conn) {
die("Connection failed: " . mysqli_connect_error());
}
$sql = "SELECT id, firstname, lastname FROM MyGuests WHERE lastname='Doe'";
$result = mysqli_query($conn, $sql);
if (mysqli_num_rows($result) > 0) {
// output data of each row
while($row = mysqli_fetch_assoc($result)) {
echo "id: " . $row["id"]. " - Name: " . $row["firstname"]. " " . $row["lastname"]. "<br>";
}
} else {
echo "0 results";
}
mysqli_close($conn);
?>
Misolni ishga tushirish »
Natijani HTML jadvaliga qo‘ying
Bu yerda biz natijani HTML jadvaliga joylashtiramiz:
Misol - MySQLi obyektga yo‘naltirilgan
<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";
// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$sql = "SELECT id, firstname, lastname FROM MyGuests WHERE lastname='Doe'";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
echo "<table><tr><th>ID</th><th>Name</th></tr>";
// output data of each row
while($row = $result->fetch_assoc()) {
echo "<tr><td>".$row["id"]."</td><td>".$row["firstname"]." ".$row["lastname"]."</td></tr>";
}
echo "</table>";
} else {
echo "0 results";
}
$conn->close();
?>
Misolni ishga tushirish »
PDO yordamida ma’lumotlarni tanlang va filtrlang
Quyidagi misol MyGuests jadvalidan identifikator, ism va familiya ustunlarini tanlaydi, bu yerda familiya "Doe" bo‘ladi va uni HTML jadvalida ko‘rsatadi:
Misol - PDO
<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";
try {
$conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
// set the PDO error mode to exception
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
} catch(PDOException $e){
die("Could not connect. " . $e->getMessage());
}
try {
$sql = "SELECT id, firstname, lastname FROM MyGuests WHERE lastname='Doe'";
// Execute the SQL query
$result = $conn->query($sql);
// Process the result set
if ($result->rowCount() > 0) {
echo "<table><tr><th>ID</th><th>Firstname</th><th>Lastname</th></tr>";
// Output data of each row
while($row = $result->fetch()) {
echo "<tr>";
echo "<td>" . $row['id'] . "</td>";
echo "<td>" . $row['firstname'] . "</td>";
echo "<td>" . $row['lastname'] . "</td>";
echo "</tr>";
}
echo "</table>";
unset($result);
else {
echo "No records found.";
}
} catch(PDOException $e) {
echo "Error: " . $e->getMessage();
}
$conn = null;
?>
W3Schools Pathfinder
Yutuqlaringizni kuzating – bu bepul!