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MySQLi UPDATE

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MySQLi UPDATE

Asha only reaches for MySQLi UPDATE when fetch marks by roll has to stay correct in the college DB.

For MySQLi UPDATE, a .php page is in play. Don’t blame it until you have traced fetch marks by roll.

Without MySQLi UPDATE, the college DB gets messy and fetch marks by roll is hard to trust.

Asha ships MySQLi UPDATE in the college DB. That is the use case worth saying.

If fetch marks by roll breaks under MySQLi UPDATE, check string-concat SQL first.

MySQLi UPDATE is not a lonely heading. Asha ties it to fetch marks by roll.

One breath for MySQLi UPDATE, then fetch marks by roll, then string-concat SQL. Sit down.

Exam tip

Board: fetch marks by roll. Dry-run MySQLi UPDATE. Name the trap: string-concat SQL.

Example

<?php
// PDO sketch (connection details omitted)
// $pdo = new PDO($dsn, $user, $pass);
// $stmt = $pdo->prepare("SELECT id, name FROM users WHERE id = ?");
// $stmt->execute([1]);
// $row = $stmt->fetch();
$demo = ["id" => 1, "name" => "Asha"];
echo $demo["name"];

MySQLi UPDATE — use prepared statements with PDO/MySQLi — never concatenate raw SQL.

Short notes

DefMySQLi UPDATE — Asha uses it for fetch marks by roll in the college DB.
RuleMySQLi UPDATE → prepared statement.
RememberMySQLi UPDATE + a .php page (the college DB).
UseMySQLi UPDATE in the college DB (fetch marks by roll).
TrapMySQLi UPDATE — string-concat SQL.
ExMySQLi UPDATE → fetch marks by roll.

<?php // PDO sketch (connection details omitted) // $pdo = new PDO($dsn, $user, $pass); // $stmt = $pdo->prepare("SELECT id, name FROM users WHERE id = ?"); // $stmt->execute([1]); // $row = $stmt->fetch(); $demo = ["id" => 1, "name" => "Asha"]; echo $demo["name"];

MySQLi UPDATE

Example

Short notes

Questions

MySQLi UPDATE

Example

Short notes

Questions