Please explain tep_db_query() format

[dhobson]

Can someone please explain the tep_db_query() function format? In this code snippet:
$category_query = tep_db_query("select cd.categories_name, cd.categories_heading_title, cd.categories_description, c.categories_image from " . TABLE_CATEGORIES . " c, " . TABLE_CATEGORIES_DESCRIPTION . " cd where c.categories_id = '" . $current_category_id . "' and cd.categories_id = '" . $current_category_id . "' and cd.language_id = '" . $languages_id . "'");

why are cd. and c. used instead of the full table names? Also, what about "cd where c.categories_id".

The cd. and the c. are supposed to be table names, but I can't find where they are defined no matter how much I search.

Please point me to a tutorial or ref man if you know of one also.

[Arpit]

cd, and c are not table names, they r alias, keeps the query looking short and neat, for more info look here:

http://dev.mysql.com/doc/mysql/en/legal-names.html

table names are defined in catalog/includes/database_tables.php, the function "tep_db_query" itself can be found in catalog/includes/functions/database.php

[dhobson]

Thank you. And yes, they are alias' but where do you define them in oscommerce. I don't see cd, and c and i've been searching.

[dhobson]

[quote="dhobson"]Thank you. And yes, they are aliasIs this the code snippet that creates the definition? TABLE_CATEGORIES . " c, " . TABLE_CATEGORIES_DESCRIPTION . " cd

[developer_x]

Yeah it is. You dont' have to define cd and c some where else except the query you pasted in your thread.