Question

I’m sure this is something really simple that I’m overlooking, but MS SQL is new to me — I am (or at least thought I was) fairly comfortable with basic MySql though.

SELECT l.link_id, l.link_allcount, d.desc_id, d.desc_count, d.desc_text, h.hour_17,   dl.day_19 
FROM lnktrk_links AS l, lnktrk_hourly AS h, lnktrk_daily AS dl 
LEFT JOIN lnktrk_descriptions AS d ON l.link_id = d.link_id 
WHERE l.link_id = h.link_id AND l.link_id = dl.link_id AND l.link_is_click = 1

The error I get is:

'The multi-part identifier "l.link_id" could not be bound.

However l.link_id definitely exists. The following query without the join works as expected:

SELECT l.link_id, l.link_allcount, d.desc_id, d.desc_count, d.desc_text, h.hour_17, dl.day_19 
FROM lnktrk_links AS l, lnktrk_hourly AS h, lnktrk_daily AS dl, lnktrk_descriptions AS d 
WHERE l.link_id = h.link_id AND l.link_id = dl.link_id AND d.link_id = l.link_id AND l.link_is_click = 1

Answer 1

I think it is that the syntax binds

lnktrk_daily AS dl 
LEFT JOIN lnktrk_descriptions AS d 
    ON l.link_id = d.link_id 

more tightly than the comma-separated clauses so you don’t have an l in that part

What you have is grouped as:

SELECT l.link_id, l.link_allcount, d.desc_id, d.desc_count, d.desc_text, h.hour_17,   dl.day_19 
FROM lnktrk_links AS l, lnktrk_hourly AS h, 
( lnktrk_daily AS dl 
  LEFT JOIN lnktrk_descriptions AS d 
  ON l.link_id = d.link_id )
WHERE l.link_id = h.link_id AND l.link_id = dl.link_id AND l.link_is_click = 1