Four different types of tables base on how data store:

  • Permanent tables (i.e., created using the create table statement)
  • Derived tables (i.e., rows returned by a subquery and held in memory)
  • Temporary tables (i.e., volatile data held in memory)
  • Virtual tables (i.e., created using the create view statement)

Derived tables(subquery-generated)

mysql> SELECT concat(cust.last_name, ', ', cust.first_name) full_name 
-> FROM 
-> (SELECT first_name, last_name, email 
	-> FROM customer 
	-> WHERE first_name = 'JESSIE' 
	-> ) cust;

Temporary tables

Data inserted into a temporary table will disappear at some point (generally at the end of a transaction or when your database session is closed)

mysql> CREATE TEMPORARY TABLE actors_j 
-> (actor_id smallint(5), 
-> first_name varchar(45), 
-> last_name varchar(45) 
-> );

Views

Learning SQL - Views