Table aliases

[fireshark]

What are they? I've seen them used in the phpBB and IPB source code

where they have some long table query and instead of saying

$table_prefix . "_posts"

it says p.posts

anypme know/use that?

[Whatcha]

Never used it myself sql tend to be short working upto larger ones

However it could be as u say an aliaes ie
select * AS alises from tbl
it may be setting the table to an aliases somewhre
select * from tbl AS alises

Probaly wrong but not toto strong on mysql

[Poster]

An alias is an alternative name for a table. They are actually used to reduce the length of a query.

For example, instead of writing

select employee.empname, dept.empdept from employee, dept where employee.empid =dept.empid

you can write by defining an alias as below.

select e.empname, d.empdept from employee e, dept d where e.empid = d.empid

where employee and dept are table names. empname is a column in employee table and empdept is a column in empdept table.

[weirfire]

Its so you can compare the same named fields from different tables

select a.customer_name, b.customer_address FROM customers a, customer_details b WHERE a.customers_id = b.customers_id

[eric]

this is normal practise to aviod ambiguaty by having a table alias or column alias too when you use a large join queries. it normally happends when the same column exits in multiple tables.

[harry]

use views when you need to join more than 3 tables in your queries, because joining more tables with aliases with slow down your query