UPDATE & DELETE
UPDATE table SET column = value WHERE condition — WHERE, clause, ke, BINA, UPDATE, karne, se, SAARI, rows, update, ho, jaayengi, jo, EXTREMELY, DANGEROUS, hai. Multiple, columns, comma-separated, mein, update, kiye, ja, sakte, HAIN.
DELETE FROM table WHERE condition — WHERE, clause, ke, BINA, DELETE, karne, se, POORI, TABLE, ke, rows, delete, ho, jaayenge (TABLE, khud, nahi).
-- Safe update, with WHERE:
UPDATE users SET status = 'inactive' WHERE last_login < '2023-01-01';
-- DANGEROUS — WHERE, ke, bina:
-- UPDATE users SET status = 'inactive'; -- SAARI rows, affect, hongi!
DELETE FROM users WHERE status = 'inactive';- UPDATE table SET col = val WHERE condition = specific, rows, modify, karta, hai
- WHERE, ke, bina, UPDATE/DELETE, SAARI, rows, ko, AFFECT, karta, hai
- Production, mein, pehle, SELECT, se, verify, karna, SAFE, practice, hai
MySQL, mein, UPDATE, statement, ke, saath, JOIN, use, kiya, ja, sakta hai — DUSRI, table, ke, data, ke, basis, PAR, update, karne, ke, liye, useful, hai.
UPDATE orders
JOIN users ON orders.user_id = users.id
SET orders.status = 'priority'
WHERE users.membership = 'premium';TRUNCATE TABLE, poori, table, ke, saare, rows, instantly, delete, kar, deta hai (WHERE, clause, ALLOW, nahi, hota) — DELETE, se, FASTER, hai, LEKIN, triggers, fire, nahi, karta, aur, rollback, karna, TRANSACTIONS, mein, MUSHKIL, hota, hai.