I have two tables named lines and attribute_values. From that I want to select the fields name from the lines tables with conditions given in the MySQL query below:
select distinct a.name
from lines a join attribute_values b
where a.advertiser_id = 280
and a.id = b.line_id
and b.name in (11, 18)
and b.value != 0;
How do I write this query using Ruby code?
Line.joins("a LEFT JOIN attribute_values b ON a.id = b.line_id").select("DISTINCT(a.name)").where("b.value != ? AND b.name in (?) AND a.advertiser_id = ?", 0, [11, 18], 280)
Assume
Line has_many attribute_values
Try this
Line.joins(:attribute_values).select("DISTINCT(lines.name)").where("lines.advertiser_id = ? AND attribute_values.name IN (?) AND attribute_values.value != ?", 280, [11,18], 0)
To get distinct value you have to apply uniq.
Lines.joins(:attribute_values).where('lines.advertiser_id = ? AND attribute_values.name in ? AND attribute_values.value <> ?', 280, [11, 18], 0).uniq
Related
I almost spent a day to optimize this query:
SELECT
prod. *,
cat.slug category_slug,
sup.bname bname,
sup.slug bname_slug
FROM bb_admin.bb_directory_products AS prod
LEFT JOIN bb_admin.bb_categories_products AS cat
ON prod.primary_category_id = cat.category_id
LEFT JOIN bb_admin.bb_directory_suppliers AS sup
ON prod.supplier_id = sup.supplier_id
LEFT JOIN bb_admin.bb_directory_suppliers AS credit_sup
ON prod.credit_supplier_id = credit_sup.supplier_id
LEFT JOIN bb_admin.bb_directory_suppliers AS photo_sup
ON prod.photo_supplier_id = photo_sup.supplier_id
WHERE (
prod.status = '1'
OR prod.status = '3'
OR prod.status = '5'
)
AND (
sup.active_package_id != '1'
OR sup.active_package_id != '5'
OR sup.active_package_id != '6'
OR prod.supplier_id = '0'
)
AND (
sup.supplier_id = '1989'
OR credit_sup.supplier_id = '1989'
OR photo_sup.supplier_id = '1989'
)
GROUP BY prod.product_id
ORDER BY prod.priority_index ASC
Can you help me to optimized this query?
Update your column data types to be INT or one of its variants, since the ones you are checking against are all integer IDs (assumption).
Create indexes on following columns(if possible in all tables):
prod.status
supplier_id
active_package_id
Use IN clause instead of concatenating OR segments.
I'll be putting the updated WHERE clause here:
WHERE prod.status IN(1, 3, 5)
AND ( sup.active_package_id NOT IN(1, 5, 6)
OR prod.supplier_id = 0
)
AND 1989 IN (prod.supplier_id, prod.credit_supplier_id, prod.photo_supplier_id)
I have two table for a multiple choice questionnaire (each user answers a series of questions):
users (userID, name, email)
votes (voteID, userID, questionID, answerID)
Sample data (users):
0, Some Name, some#thing.com
1, Other Name, some#one.com
Sample data (votes):
0, 1, 1, 1
1, 1, 2, 2
2, 1, 3, 2
I would like select all users who has the correct answers.
I tried this (where I've hardcoded the answers in):
$sql = "SELECT users.userID, users.name, users.email FROM users
INNER JOIN votes ON (users.userID = votes.userID)
WHERE (votes.questionID = '1' AND votes.answerID = '1')
AND (votes.questionID = '2' AND votes.answerID = '2')
AND (votes.questionID = '3' AND votes.answerID = '2')
AND (votes.questionID = '4' AND votes.answerID = '3')
AND (votes.questionID = '5' AND votes.answerID = '1')
GROUP BY users.userID";
But this doesn't return anything.
I've also tried something like this (where I've also hardcoded the answers in):
$sql = "SELECT users.userID, users.name, users.email FROM users
INNER JOIN transfertipsvotes ON (users.userID = transfertipsvotes.userID)
WHERE (transfertipsvotes.questionID = '1' AND transfertipsvotes.answerID = '1') GROUP BY users.userID
UNION
SELECT users.userID, users.name, users.email FROM users
INNER JOIN transfertipsvotes ON (users.userID = transfertipsvotes.userID)
WHERE (transfertipsvotes.questionID = '2' AND transfertipsvotes.answerID = '2') GROUP BY users.userID
UNION
SELECT users.userID, users.name, users.email FROM users
INNER JOIN transfertipsvotes ON (users.userID = transfertipsvotes.userID)
WHERE (transfertipsvotes.questionID = '3' AND transfertipsvotes.answerID = '2') GROUP BY users.userID";
But this just returns all users with one correct answer.
How do I make the correct query to select all users with the correct answers?
As far as I can see it now you need to use an INNER JOIN for each question, so each inner join will look like this:
INNER JOIN votes AS q1 ON (users.userID = q1.userID) AND q1.questionID = '1' AND q1.answerID ='1'
Repeat this for each question and you can check it.
If i understood you correctly, you want users who have answered all questions correct. In that case you should use INTERSECT instead of UNION
But for this you are hitting the table as many times as your questions. Its better to use OR clause in where "((question1 and Answer1) or (question2 and Answer2))". and at last do a group based on userid and get count of correct answer and fetch only those members whose has all correct answer.
i have problem with join table and use multiple conditions...
My code:
SELECT * FROM
(SELECT sid, MAX(info_date_add) AS max_info_date_add FROM skiresort GROUP BY sid) skiresort_max
INNER JOIN skiresort
ON
skiresort_max.sid = skiresort.sid AND
skiresort_max.max_info_date_add = skiresort.info_date_add
JOIN skiresort_theme_value
ON skiresort_theme_value.skiresort_id = skiresort.id
WHERE
skiresort_theme_value.skiresort_theme_id = '1' AND
skiresort_theme_value.skiresort_theme_id = '2' AND
skiresort_theme_value.skiresort_theme_id = '4'
GROUP BY skiresort.sid
ORDER BY skiresort.title_en
In this code, the conditions are in WHERE clausule. I also tried to put in into JOIN ON (...) but it also didn't work.
When i have only one condition it works. I read some articles about using OR instead of AND, it worked but not as i expected. I need to search only rows with certain IDs (multiple).
why not use this instead of many conditions.
WHERE
skiresort_theme_value.skiresort_theme_id in (1, 2,4)
GROUP BY skiresort.sid
HAVING COUNT(DISTINCT skiresort_theme_value.skiresort_theme_id) = 3
ORDER BY skiresort.title_en
when add condition to WHERE, condition must be from FROM tbl
add condition JOIN ON
Try this:
SELECT * FROM
(SELECT sid, MAX(info_date_add) AS max_info_date_add FROM skiresort GROUP BY sid) skiresort_max
INNER JOIN skiresort
ON
skiresort_max.sid = skiresort.sid AND
skiresort_max.max_info_date_add = skiresort.info_date_add
JOIN skiresort_theme_value
ON (skiresort_theme_value.skiresort_id = skiresort.id AND skiresort_theme_value.skiresort_theme_id = '1' AND skiresort_theme_value.skiresort_theme_id = '2' AND skiresort_theme_value.skiresort_theme_id = '4')
GROUP BY skiresort.sid
ORDER BY skiresort.title_en
Here is the case:-
I want to join 2 tables. Lets say table a and b
SELECT *
FROM a
JOIN b ON a.id = b.id AND b.status = '1'
Here is the problem:
b.status = '1'
should only be added when
b.stage in (1, 3, 5, 6, 8)
How can I add such condition in ON clause ?
Like
ON a.id = b.id
CASE
IF (b.stage in (1, 3, 5, 6, 8))
THEN
AND b.status = '1'
END
Your condition is logically the same as "either stage is not in the list or status is 1":
SELECT *
FROM a
JOIN b ON a.id = b.id
AND (b.stage not in (1, 3, 5, 6, 8) OR b.status = '1')
There are two tables - incoming tours(id,name) and incoming_tours_cities(id_parrent, id_city) where id_parrent is id from first table.
Here is the query i wrote
SELECT t.cities
FROM `incoming_tours` t
JOIN `incoming_tours_cities` tc0 ON tc0.id_parrent = t.id
AND tc0.id_city = '1'
JOIN `incoming_tours_cities` tc1 ON tc1.id_parrent = t.id
AND tc1.id_city = '6'
And now, what is the question...
Why i can't write both conditions in single join?(i.e. i can, but it returns empty result.)
as i understand joins, when i wrote
JOIN incoming_tours_cities tc ON tc.id_parrent = t.id
it must return the list of rows where the condition is true. isn't it?
So why i can't write
SELECT t.cities
FROM `incoming_tours` t
JOIN `incoming_tours_cities` tc ON tc.id_parrent = t.id
AND tc.id_city = '1'
AND tc.id_city = '6'
And maybe there is more efficient method to rich same effect(because in my structure the count of conditions can be very big)
Thanks much
the value of tc.id_city cannot be both '1' and '6' simultaneously. I think you want an OR rather than an AND:
SELECT t.cities
FROM `incoming_tours` t
JOIN `incoming_tours_cities` tc ON tc.id_parrent = t.id
AND (tc.id_city = '1'
OR tc.id_city = '6')
Think of it this way. If you ask for rows from incoming_tour_cities for which the id_city value is '1' and is also at the same time '6', how many rows will you match?
What you really want is:
SELECT t.cities
FROM `incoming_tours` t
JOIN `incoming_tours_cities` tc ON tc.id_parrent = t.id
WHERE (tc.id_city = '1' OR tc.id_city = '6')
or, more compactly:
SELECT t.cities
FROM `incoming_tours` t
JOIN `incoming_tours_cities` tc ON tc.id_parrent = t.id
WHERE tc.id_city IN ('1', '6')
An alternative answer based on the user's clarification that the first query is the one he wants to duplicate.
Here is the only "short cut" way I know of doing this, where "short cut" means not performing two independent tests (using JOINs or EXISTs clauses):
SELECT t.cities
FROM `incoming_tours` t
JOIN `incoming_tours_cities` tc ON tc.id_parrent = t.id
WHERE tc.id_city IN ('1', '6')
GROUP BY t.cities HAVING COUNT(DISTINCT tc.id_city) > 2