Ravindra BagaleCourses & study guides

11. MySQL Part 2: UPDATE, ALTER, DELETE, Keys, Constraints and Users

By Last updated:

Chala mitrano, kaal aapan data vachayla shiklo. Aaj data badlayla, table chi rachna badlayla, data kaadhayla aani database la niyam (keys, constraints) lavayla shikuya. Shevti users aani GRANT – kon kay karu shakto. Ha chapter khup important aahe, lakshat theva: ek chukicha UPDATE kiwa DELETE purna table udavto. Mhanun safe update mode aani transactions pan shikuya. Ghabru naka, pratyek query aadhi SELECT ne test karaychi – hi savay aajpasun.

What you will learn in this chapter

  • UPDATE with WHERE, and testing with SELECT first
  • Safe update mode (SQL_SAFE_UPDATES, error 1175) and transactions
  • ALTER TABLE: add, modify, rename and drop columns, rename tables
  • DELETE, TRUNCATE and DROP, and the exact differences between them
  • All keys: primary, foreign, unique, composite, candidate, super and alternate
  • Constraints: NOT NULL, DEFAULT, CHECK, AUTO_INCREMENT
  • Creating users, GRANT, REVOKE and least privilege; backup with mysqldump

Concepts in this chapter

  1. 11.1UPDATE
  2. 11.2Safe Update Mode, Error 1175 and Transactions
  3. 11.3ALTER TABLE: Add, Modify, Rename and Drop Columns
  4. 11.4DELETE, TRUNCATE and DROP
  5. 11.5Keys: Primary, Foreign, Unique, Composite, Candidate, Super, Alternate
  6. 11.6Constraints: NOT NULL, DEFAULT, CHECK, AUTO_INCREMENT
  7. 11.7Users, GRANT, REVOKE and Least Privilege

The chapter recap is at the end of the last concept page.