PHP Database Query in Hindi
RGPV University / DIPLOMA_CSE / Web Technology
PHP Database Query in Hindi
PHP Database Query in Hindi
PHP (Hypertext Preprocessor) ek server-side scripting language hai jo dynamic web applications banane ke liye istemal hoti hai. Database queries ka use karke aap PHP ke through data ko manage, store aur retrieve kar sakte hain. Database queries ko SQL (Structured Query Language) ke roop mein likha jata hai. Is article mein hum PHP mein commonly used database queries ko samjhenge aur unhe Hindi mein detail mein samjhaenge.
1. SELECT Query in PHP
SELECT query ka use database se data retrieve karne ke liye kiya jata hai. Is query se aap specific columns ya puri table ka data fetch kar sakte hain. SELECT query ka basic syntax kuch is tarah hota hai:
query($sql);
if ($result->num_rows > 0) {
while($row = $result->fetch_assoc()) {
echo "column1: " . $row["column1"] . " - column2: " . $row["column2"] . "
";
}
} else {
echo "0 results";
}
?>
Yahaan pe `SELECT column1, column2` ka matlab hai ki hum table se `column1` aur `column2` ka data fetch kar rahe hain. Agar aap table ka saara data chahte hain toh `*` ka use karte hain, jaise:
2. INSERT Query in PHP
INSERT query ka use database mein naye records insert karne ke liye kiya jata hai. Is query ka syntax kuch is tarah hota hai:
query($sql) === TRUE) {
echo "New record created successfully";
} else {
echo "Error: " . $sql . "
" . $conn->error;
}
?>
Yahaan pe `table_name` ka matlab aapke database ka table hai, jisme aap data insert karna chahte hain. `column1, column2` wo columns hain jisme aap data insert karenge, aur `value1, value2` wo values hain jo aap insert karna chahte hain.
3. UPDATE Query in PHP
UPDATE query ka use kisi existing record ko modify karne ke liye kiya jata hai. Agar aap kisi record ki value change karna chahte hain, toh UPDATE query ka use hota hai. Iska syntax kuch is tarah hota hai:
query($sql) === TRUE) {
echo "Record updated successfully";
} else {
echo "Error: " . $sql . "
" . $conn->error;
}
?>
Yahaan pe `SET column1='new_value1'` ka matlab hai ki hum `column1` ko `new_value1` se update kar rahe hain. `WHERE condition` ka use karna zaroori hai, varna saare records update ho jayenge.
4. DELETE Query in PHP
DELETE query ka use kisi record ko database se delete karne ke liye kiya jata hai. Iska syntax kuch is tarah hota hai:
query($sql) === TRUE) {
echo "Record deleted successfully";
} else {
echo "Error: " . $sql . "
" . $conn->error;
}
?>
Yahaan pe `WHERE condition` ka use karna bahut zaroori hai, kyunki bina condition ke aapke table ke sabhi records delete ho sakte hain.
5. PHP Database Connection
PHP mein database se connect karne ke liye `mysqli` ya `PDO` ka use kiya jata hai. Yahaan pe hum `mysqli` ke through database connection ka example dekhenge. Iska basic syntax kuch is tarah hota hai:
connect_error) {
die("Connection failed: " . $conn->connect_error);
}
?>
Yahaan pe `localhost` aapka server address hai, `username` aur `password` wo credentials hain jo aapke database ke liye hote hain, aur `database_name` wo database ka naam hai jise aap connect karna chahte hain.
6. Error Handling in PHP Database Queries
PHP mein jab aap database queries execute karte hain, toh error handling ka bahut dhyaan rakhna padta hai. Aap `try-catch` block ka use karke errors ko handle kar sakte hain. Yeh aapke code ko robust banaata hai. Example ke liye:
connect_error) {
throw new Exception("Connection failed: " . $conn->connect_error);
}
$sql = "SELECT * FROM table_name";
$result = $conn->query($sql);
if (!$result) {
throw new Exception("Query failed: " . $conn->error);
}
} catch (Exception $e) {
echo "Error: " . $e->getMessage();
}
?>
Is example mein agar koi connection ya query error hota hai toh wo exception throw ho jaata hai aur aap usse handle kar sakte hain.
7. Advanced Query Techniques
Agar aap complex queries likhna chahte hain, jaise multiple joins, subqueries, ya aggregate functions, toh aapko advanced SQL techniques ka use karna padega. Jaise ki:
50000";
?>
Yahaan pe `INNER JOIN` ka use kiya gaya hai, jo `employees` aur `departments` table ko join karta hai. Is tarah se complex data ko fetch kiya ja sakta hai.