A quick guide to mysql tables amp queries inserting data

A Quick Guide To MySQL Tables Queries This is a Quick reference Guide for MySQL x MySQL is a relational database management system RDBMS based on SQL Structured Query Language MySQL is available under GNU public license and through subscription to MySQL Network for business applications It runs on Unix iMac and Windows and provides rich API for many programming languages including C C Java Perl Python Ruby and PHP Database Queries List all databases SHOW databases Select the database USE USE university Create a database CREATE DATABASE CREATE DATABASE university Delete a database DROP DATABASE DROP DATABASE university Rename a database ALTER DATABASE RENAME ALTER DATABASE university RENAME faculty Table Queries Create a table CREATE TABLE ? CREATE TABLE teachers name varchar age INT List all tables in the database SHOW tables Show table format with column names and data types DESCRIBE DESCRIBE teachers Modify the structure of table ALTER TABLE ALTER TABLE teachers DROP COLUMN salary ALTER TABLE teachers ADD COLUMN salary INT ALTER TABLE teachers CHANGE ?rstName name VARCHAR Delete the table DROP TABLE DROP TABLE teachers Retrieving Data SELECT FROM WHERE Retrieve from all columns SELECT FROM SELECT FROM teachers Retrieve from selected columns SELECT FROM SELECT id name FROM teachers Retrieve from selected tables SELECT FROM SELECT teachers name students name FROM teachers students Retrieve unique values SELECT DISTINCT FROM SELECT DISTINCT name FROM teachers Retrieve data satisfying a given condition SELECT FROM WHERE SELECT name FROM teachers WHERE age Retrieve data satisfying multiple conditions SELECT FROM WHERE AND SELECT name FROM teachers WHERE age AND gender ? female ? Inserting Data INSERT INTO VALUES INSERT INTO teachers id name age VALUES NULL ? John ? ? ? Loading Data from Files LOAD DATA LOCAL INFILE ? ? INTO TABLE LOAD DATA LOCAL INFILE ? ?le sql ? INTO TABLE teachers This is very convenient to load data directly from ?les when you have thousands of entries Modifying Data UPDATE SET AND WHERE UPDATE teachers SET status ? enrolled ? WHERE fees ? paid ? Deleting Data DELETE FROM WHERE DELETE FROM teachers WHERE fees ? paid ? Pattern Matching Examples SELECT FROM teachers WHERE name LIKE ? j ? Wildcard selects joe john jones etc SELECT FROM teachers WHERE name LIKE ? ? Selects character values SELECT FROM teachers WHERE name REGEXP ? A ? Selects all entries beginning with A SELECT FROM teachers WHERE name REGEXP ? p ? Selects all entries ending with p abc abc A-Z a-z - match a b or c match all expect a b or c match uppercase match lowercase match any digit match zero or more instances match one or more instances match zero or one instance match any single char match the beginning ? ? match the end separates alternatives The BETWEEN operator is used to ?lter the result set within a certain range The values can be numbers text or dates n m match at least n times but notmore than m times n

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