Mysql/CheatSheet: Difference between revisions

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** NOT NULL
** NOT NULL
** UNIQUE
** UNIQUE
** PRIMARY KEY
** PRIMARY KEY   (NOT NULL and UNIQUE)
** FOREIGN KEY
** FOREIGN KEY
** CHECK
** CHECK

Revision as of 15:05, 15 June 2020

Databases

  • Create
CREATE DATABASE [IF NOT EXISTS] database_name;
  • Use
USE database_name;
  • Delete
DROP DATABASE [IF EXISTS] database_name;
  • List all
SHOW DATABASE;
  • Storage Engines
    • MyISAM (optimized for compression and speed. portable. not transaction safe. used to be default)
    • InnoDB (optimized for speed. portable. portable. default)
    • MERGE
    • MEMORY (HEAP)
    • ARCHIVE
    • CSV
    • FEDERATED

Tables

  • list
SHOW TABLES;
  • create
CREATE TABLE [IF NOT EXISTS] table_name(
  column1 datatype constraint,
  column2 datatype constraint
);
CREATE TABLE IF NOT EXISTS cars(
  vehicle_id INT AUTO_INCREMENT PRIMARY KEY,
  title VARCHAR(255) NOT NULL,
  first_seen DATE,
  description TEXT
);
  • constraints
    • NOT NULL
    • UNIQUE
    • PRIMARY KEY (NOT NULL and UNIQUE)
    • FOREIGN KEY
    • CHECK
    • DEFAULT
    • INDEX

other