SQL

From Coder Merlin
Within these castle walls be forged Mavens of Computer Science ...
— Merlin, The Coder


Configuration File[edit]

Employees[edit]

Create a file named ~/.my.cnf in your home directory containing the following:

[client]
host=db
database=employees
user=employees_user
password=N@!S%9poX5HE,CdPJ6_2

Sakilla[edit]

[client]
host=db
database=sakila
user=sakila-user
password="J4wZwE:}.5RySc-"

LOGIN Topics[edit]

  • Successfully log in to a database using command line options
  • Successfully log in to a database using a configuration file

SHOW Topics[edit]

  • Show all tables in a specified database
  • Show all columns from a specified table

Column Types[edit]

  • CHAR
  • VARCHAR
  • TEXT
  • BLOB
  • ENUM
  • SET
  • BOOLEAN
  • INT
  • FLOAT
  • DOUBLE
  • DECIMAL
  • DATE
  • TIME
  • DATETIME
  • TIMESTAMP
  • NULL

SELECT Topics[edit]

  • Selecting constants
  • Select all records from a specified table
  • Select specific columns from a specified table
  • Select non-repeating (distinct) records from a specified table
  • Column aliases

Ordering Records[edit]

  • Ordering records with a single column
  • Ordering records with multiple columns

Filters[edit]

  • Using where
  • Using logical operators
  • Using NULL
  • Using LIKE and wildcards
  • Using IN
  • Using BETWEEN

Aggregate Queries[edit]

  • Count
  • Average
  • Maximum
  • Minimum
  • Sum

Joins[edit]

  • Inner
  • Left
  • Right
  • Outer
  • Self

Unions[edit]

  • Union (distinct)
  • Union (all)