Question

I have a table:

item_id  | property_id | value |
================================
1        |      100    |   1   |
1        |      101    |   1   |
1        |      102    |   0   |
2        |      100    |   1   |
2        |      101    |   1   |
2        |      102    |   1   |
2        |      120    | black |
3        |      100    |   1   |
3        |      101    |   0   |
3        |      102    |   1   |
4        |      121    |  big  |
...

I would like to perform “AND” search by a form with multiple checkboxes and select menus (each checkbox and select menu have name like ‘property_id’).

Example:

1. When I check checkbox 100 and 101, desire result of query is item_id = 1, 2.
2. When I check checkbox 100, 101 and choose ‘black’ from select menu 120, desire result is item_id = 2.
3. When I check checkbox 100, 101, choose ‘black’ from select menu 120, and choose ‘big’ from select menu 121, desire result is item_id = NULL.

Number of checked properties (checkboxes and selectmenus) may vary.

I tried:

SELECT item_id
FROM yourtable
WHERE property_id IN (100, 101)
AND value = 1
GROUP BY item_id
HAVING COUNT(DISTINCT property_id) = 2

But it’s only for checkboxes and values 0 or 1. I have problem to implement it with select menus (example 2. or 3.)

I hope that explains what I’m trying to do.
Thanks in advance!

Answer 1

With minimum changes to your query:

SELECT item_id
FROM yourtable
WHERE property_id IN (100, 101)
  AND value = 1
   OR property_id = 120 
  AND value = 'black'
GROUP BY item_id
HAVING COUNT(DISTINCT property_id) = 3 ;

which is equivalent to:

SELECT item_id
FROM yourtable
WHERE property_id = 100  AND  value = 1 
   OR property_id = 101  AND  value = 1
   OR property_id = 120  AND  value = 'black'
GROUP BY item_id
HAVING COUNT(DISTINCT property_id) = 3 ;