SQL Order question

182x

Hey guys, I have done a basic query:

select d, f from acc where cId=  $_session cd;

So far when using this query with php it displays the data in the order it was entered which is what I want but I was wondering will it always do this or will i need some form of order by? Thanks.

conjurer

select d, f from acc where cId= $_session cd;

That will return rows from your table in the order that they are found in your table.

If you want the results sorted you would need to add an order by:

Select d, f from acc where cId=  $_session cd [B]ORDER BY[/B] somevalue;

182x

Thanks, will the order they are found be from starting at the top of the table or the bottom or random?

conjurer

This should explain it to you:
http://dev.mysql.com/doc/refman/4.1/en/sorting-rows.html

182x

Hi thanks again for you reply just to be clear without the order by would the out put always be in the order as shown below?

SELECT lastName, firstName FROM test;

The database table test:

lastName 	 firstName      id
Carr                 James           1
Marks              Alex               2
Brown             Kim                3
Bow                Tim                4


The query output:

lastName 	firstName

Carr                James
Marks             Alex
Brown            Kim
Bow               Tim

conjurer

If that is the way it resides in your database then that is the way it will come out.

But down the road if you have deleted rows and added rows and sequences get messed up then you might have:

Code:

SELECT lastName, firstName FROM test;

The database table test:

lastName 	 firstName      id
[deleted 1]
Marks              Alex               2
Brown             Kim                3
[deleted 4]
Carr                 James           5
Bow                Tim                6


The query output in this case without an Order by:

lastName 	firstName
Marks             Alex
Brown            Kim
Carr                James
Bow               Tim