vimwiki/tech/sql.wiki

= SQL =

Stuctered Query Language is a language that describes a method of fetching and
describing the relationship between different types of data

== Views ==

A view can be created with the following command

{{{
CREATE VIEW [view_name] AS
SELECT column1, column2, ...
FROM table
WHERE condition;
  }}}

For example, this view returns all products witha price higher than the average
price of the table

{{{
CREATE VIEW [Products above average price] AS
SELECT Name, Price
FROM Products
WHERE Price > (SELECT AVG(Price) FROM Products)

SELECT * FROM [Prodcuts above average price]
  }}}

== Acess control commands ==

Two commands for managing access rights

* grant
  * used to grant one or more access rights or can be used to assign a user to
    a role
* revoke
  * revokes the acess rights

Typical access rights include

* select
* insert update
* delete
* references

== Also see ==

[[databases]]

[[index]]