Access 2010: Syntax error (missing operator) in query expression
In Access you need parentheses when you have more than one join:
FROM (drugs as a
INNER JOIN warehouse as b
ON a.ID = b.drug_id)
INNER JOIN pharmacy as c
ON b.drug_id = c.drug_id
Just wanted to add that it gets even more messy when you have more than 2 Inner Joins. Then you need to add an extra parentheses at the beginning and to the end of each of the Inner Joins (except the last one)
Example:
FROM ((drugs as a
INNER JOIN warehouse as b
ON a.ID = b.drug_id)
INNER JOIN pharmacy as c1
ON b.drug_id1 = c1.drug_id)
INNER JOIN pharmacy as c2
ON b.drug_id2 = c2.drug_id