"lr.", "tr." ?

[sepoto]

I have a snapshot from a very long query I am working with. I searched my database for any tables named "lr" or "tr" but there are none. Does anyone know the meaning of the "lr." or the "tr.".

SELECT DISTINCT lr.cl_station_num as cl_station_num, tr.tz_utc_std_offset as tz_utc_std_offset

[justsomeguy]

Those are aliases defined somewhere else in the query.

[jeffman]

Farther along the query, is there a part like FROM some_table AS lr, another_table AS tr? This would just be creating another layer of aliases.

[sepoto]

Below is the whole query:

$query = "insert into flat_list (cl_station_num, tz_utc_std_offset, tf_station_time_zone, tf_station_call_sign, cl_tms_chan, tf_epi_title, time_adjusted, tf_title_display, tf_hdtv, cl_headend_id)	SELECT DISTINCT lr.cl_station_num as cl_station_num, tr.tz_utc_std_offset as tz_utc_std_offset, sr.tf_station_time_zone as tf_station_time_zone, sr.tf_station_call_sign as tf_station_call_sign, lr.cl_tms_chan as cl_tms_chan, p.tf_epi_title as tf_epi_title, 					s.tf_time_adj as time_adjusted,					t.tf_title_display as tf_title_display, s.tf_hdtv as tf_hdtv, lr.cl_headend_id as cl_headend_id						FROM program_category_to_title t					JOIN sports_program p on p.tf_title = t.tf_title					JOIN sports_schedule_timeadj s on s.tf_database_key = p.tf_database_key					JOIN station_record sr on sr.tf_station_num = s.tf_station_num					JOIN sat_lineup_record lr on lr.cl_station_num = sr.tf_station_num					JOIN timezone_record tr ON tr.tz_time_zone_name = sr.tf_station_time_zone and ({$date_nf} >= tr.tz_date1 and {$date_nf} < tr.tz_date2)					WHERE t.cat_id=2";

[Synook]

Well, there you go - lr is an alias for sat_lineup_record and tr is an alias for timezone_record.