Question

How can I fill gaps between rows? Im using table calendar but my query does not seem to be correct. The result is not showing the gaps..

SELECT calendar.datefield, t2.*
    FROM store_relation t1,store t3, store_product t2
            RIGHT JOIN calendar ON (DATE(t2.created) = calendar.datefield)
            WHERE (calendar.datefield BETWEEN ('2012-07-15') and ('2012-07-20'))
    AND t1.id_store_a = 1
    AND t1.id_store_b = t2.id_store
    AND t3.id = t2.id_store
    AND t2.id_product = 11
    ORDER By t2.price

Result:

datefield   |   id_product   |   id_store   |   created
2012-07-15      1                1              2012-07-15
2012-07-18      1                1              2012-07-18
2012-07-20      1                1              2012-07-20
2012-07-20      1                1              2012-07-20

I was waiting for the result

datefield   |   id_product   |   id_store   |   created
2012-07-15      1                1              2012-07-15
2012-07-16      null             null           null
2012-07-17      null             null           null
2012-07-18      1                1              2012-07-18
2012-07-19      null             null           null
2012-07-20      1                1              2012-07-20
2012-07-20      1                1              2012-07-20

Answer 1

When you have a LEFT/RIGHT JOIN and you are filtering on tables that are optionally included, the WHERE clause will leave those records out. You need to include a condition that allows for the left part of the RIGHT JOIN being missing:

WHERE (calendar.datefield BETWEEN ('2012-07-15') and ('2012-07-20'))
AND
(
   (t1.id_store_a = 1
   AND t1.id_store_b = t2.id_store
   AND t3.id = t2.id_store
   AND t2.id_product = 11)
   OR
   (t2.id_product is NULL)
)

For example, if you look at your expected output, the value of id_product is null, but you are filtering for t2.id_product = 11. So the null records are never going to match 11, and that’s why they are being left out.