Learning to write sql queries and facing some issues.
The query:
SELECT *
FROM competitions c
INNER JOIN (
SELECT competitionId, SUM(quantity) AS quantity
FROM tickets
GROUP BY competitionId
) t ON t.competitionId = c.id
WHERE
c.winnerId IS NULL
AND t.quantity = c.maxEntries
OR
CURRENT_TIMESTAMP() >= c.endAt;
This returns only one results but should return two results.
CURRENT_TIMESTAMP() >= c.endAt;
Should also include one more record but this statement is skipped for whatever reason...
The competition table records:
The record which is marked in red square do match to the where condition. Why then it wouldn't be included?
Changing from INNER JOIN to LEFT JOIN gives desired results.
The query:
SELECT *
FROM competitions c
LEFT JOIN
(SELECT competitionId, SUM(quantity) AS quantity
FROM tickets GROUP BY competitionId
) t ON t.competitionId = c.id
WHERE
c.winnerId IS NULL AND
(t.quantity=c.maxEntries OR CURRENT_TIMESTAMP() >= c.endAt)
Related
I have Query Like This
SELECT f.ACCOUNT_ID,
f.TGL,
p.ACCOUNT_EMAILADDRESS
FROM distributor_kokola.forecast f
inner join distributor_kokola.push_distributor p on p.ACCOUNT_ID = f.ACCOUNT_ID
where f.ACCOUNT_ID NOT IN(
select ACCOUNT_ID
from distributor_kokola.forecast
where DATE_FORMAT(TGL, "%Y-%m") = DATE_FORMAT(CURDATE(), "%Y-%m")
group by ACCOUNT_ID
)
group by f.ACCOUNT_ID;
That Sub Query work but To Slow so I change it with Left Join, it work faster
SELECT f.ACCOUNT_ID,
f.TGL,
p.ACCOUNT_EMAILADDRESS
FROM distributor_kokola.forecast f
left join(
select ACCOUNT_ID
from distributor_kokola.forecast
where DATE_FORMAT(TGL, "%Y-%m") = DATE_FORMAT(CURDATE(), "%Y-%m")
group by ACCOUNT_ID
)subb on subb.ACCOUNT_ID = f.ACCOUNT_ID
inner join distributor_kokola.push_distributor p on p.ACCOUNT_ID = f.ACCOUNT_ID
group by f.ACCOUNT_ID;
But, My issue is Still Contain wrong Result,
With Not IN, query 1 select where NOT IN query 2.
How can I get like NOT IN query with left join.
Can Anyone Help Me?
thanks.
You have to add a WHERE clause to filter by the results of your LEFT JOIN. If you add an appropriate WHERE clause WHERE subb.ACCOUNT_ID IS NULL, it should work as expected (since you used a GROUP BY in your subquery, there's no danger of duplicate rows):
SELECT f.ACCOUNT_ID,
f.TGL,
p.ACCOUNT_EMAILADDRESS
FROM distributor_kokola.forecast f
left join(
select ACCOUNT_ID
from distributor_kokola.forecast
where DATE_FORMAT(TGL, "%Y-%m") = DATE_FORMAT(CURDATE(), "%Y-%m")
group by ACCOUNT_ID
) subb on subb.ACCOUNT_ID = f.ACCOUNT_ID
inner join distributor_kokola.push_distributor p on p.ACCOUNT_ID = f.ACCOUNT_ID
WHERE sub.ACCOUNT_ID IS NULL
group by f.ACCOUNT_ID;
Update
The goal of our LEFT JOIN is to find all rows in our forecast table that don't have a matching row in the subquery. Therefore, we need a WHERE clause that removes all rows with a matching row - WHERE sub.ACCOUNT_ID IS NULL fits quite nicely.
SO user #quassnoi has written a wonderful comparison of different methods to achieve this goal.
My query gets the results of these products based on if they exist in a separate table index. I am trying to get a count of all the instances where they exist so I can ORDER the results by relevance. Everything I try seems to return the variable #priority as 0. Any ideas?
Maybe it is better to use join statements?
Thank you for your help. Here is my MySQL query:
SELECT `products` . * , #priority
FROM `products`
LEFT JOIN productstypes_index ON productstypes_index.product_id = products.id
WHERE (
EXISTS (
SELECT *
FROM `productstypes_index`
WHERE `productstypes_index`.`product_id` = `products`.`id`
AND `productstypes_index`.`_type_id` = '1'
)
AND (
(
(
EXISTS (
SELECT #priority := COUNT( * )
FROM `producthashtags_index`
WHERE `producthashtags_index`.`product_id` = `products`.`id`
AND `producthashtags_index`.`producthashtag_id` = '43'
)
)
AND (
EXISTS (
SELECT #priority := COUNT( * )
FROM `producthashtags_index`
WHERE `producthashtags_index`.`product_id` = `products`.`id`
AND `producthashtags_index`.`producthashtag_id` = '11'
)
)
)
)
)
ORDER BY `updated_at` DESC;
You could do without those exists, and without variables. Also, a left join has no sense if you have an exists condition on the joined table. Then you might as well do the more efficient inner join and put the extra type condition in the join condition.
The priority can be calculated by a count over the hash tags, but only those with id in ('43', '11').
SELECT products.*
count(distinct producthashtags_index.producthashtag_id) priority
FROM products
INNER JOIN productstypes_index
ON productstypes_index.product_id = products.id
AND productstypes_index._type_id = '1'
INNER JOIN producthashtags_index
ON producthashtags_index.product_id = products.id
AND producthashtags_index.producthashtag_id in ('43', '11')
GROUP BY products.id
ORDER BY updated_at DESC;
MySQL ignores the SELECT list in EXISTS subquery, so it makes no difference what you type in there. This is documented here.
An approach using joins would look like below:
SELECT p.id,
COUNT(case when phi.product_id is not null then 1 end) AS instances
FROM products p
INNER JOIN productstypes_index pti ON pti.product_id = p.id AND pti.`_type_id` = 1
LEFT JOIN producthashtags_index phi ON phi.product_id = p.id AND phi.producthashtag_id IN (11,43)
GROUP BY p.id
ORDER BY instances DESC;
I have removed additional backticks where I believe they are not neccessary and also if your id columns in tables are integers, you do not need quotation marks.
I have an sql query that returns a list of residential units, and a subquery that is supposed to get the last entered bill for that unit.
However when I add LIMIT 1 to the subquery, no bill entries are returned? If I leave it out, I get duplicate unit rows depending on the number of bill for the unit.
select * from unit u
left join (select id as billId, unit_id, added_on, end_reading, bill_type from bills
order by id desc) b ON unit_id = u.id
where community_Id = 1
and unit_section = 7
and unit_floor in (1,2,3,4,5)
order by unit_floor, display_order asc;
Anyone know how I can the subquery result limited to 1 bill?
When using joins that duplicate your results, add a group by statement. It's an alternative of the distinct from a simple select
select * from unit u
left join (select id as billId, unit_id, added_on, end_reading, bill_type from bills
order by id desc) b ON unit_id = u.id
where community_Id = 1
and unit_section = 7
and unit_floor in (1,2,3,4,5)
group by u.id
order by unit_floor, display_order asc;
Think you will need a sub query to get the first (lowest) id for each unit_id from the bills table. Then use that to join between the unit and bills table, getting the other matching columns from bills for that lowest id
SELECT u.*, bills.*
FROM unit u
LEFT OUTER JOIN
(
SELECT unit_id, MIN(id) AS min_id
FROM bills
GROUP BY unit_id
) b ON b.unit_id = u.id
LEFT OUTER JOIN bills
ON b.unit_id = bills.unit_id
AND b.min_id = bills.id
WHERE u.community_Id = 1
AND u.unit_section = 7
AND u.unit_floor in (1,2,3,4,5)
ORDER BY u.unit_floor, u.display_order asc;
I need help writing a MySQL query. So far, none of the questions out there seem to fit my needs.
I have an order table and an order_log table. In the order_log table I make a record every time an order's status is changed. I need to display a list of the most recent status changes from the order_log table. The query I'm currently using does a JOIN on the two tables and grabs everything where order.status = order_log.status.
The problem with this is that some times an order will pass through the same status more than once. When that occurs, my query grabs every entry in the order_log table for that order and that status, but I only want the most recent log.
I tried writing a new JOIN query to grab the Max of the order_log date entry, but it's only returning 1 entry. This is what I have.
SELECT *
FROM order_status_log AS l
JOIN orders AS o ON ( l.order_id = o.id )
WHERE l.status = o.status
AND l.date = (
SELECT MAX( date )
FROM order_status_log l2
JOIN orders AS o2 ON ( l2.order_id = o2.id )
)
Any ideas?
there are many ways to do it, one is to have a separate subquery the gets the latest entry of each record: order_ID.
The result of the subquery is then joined back with the original table but has multiple conditions: that it matches the order_ID and also the latest date.
SELECT a.*, b.*
FROM `order` a
INNER JOIN order_log b
ON a.id = b.order_ID
INNER JOIN
(
SELECT order_ID, MAX(date) max_date
FROM order_log
GROUP BY order_ID
) c on b.order_ID = c.order_ID AND
b.date = c.max_date
That may help;
select olg.column1,o.column2,max(olg.date) from --You can add other columns as well
order_status_log olg
join orders o
on olg.id = o.order_id
group by olg.column1,o.column2
I am having to set up a query that retrieves the last comment made on a customer, if no one has commented on them for more than 4 weeks. I can make it work using the query below, but for some reason the comment column won't display the latest record. Instead it displays the oldest, however the date shows the newest. It may just be because I'm a noob at SQL, but what exactly am I doing wrong here?
SELECT DISTINCT
customerid, id, customername, user, MAX(date) AS 'maxdate', comment
FROM comments
WHERE customerid IN
(SELECT DISTINCT id FROM customers WHERE pastdue='1' AND hubarea='1')
AND customerid NOT IN
(SELECT DISTINCT customerid FROM comments WHERE DATEDIFF(NOW(), date) <= 27)
GROUP BY customerid
ORDER BY maxdate
The first "WHERE" clause is just ensuring that it shows only customers from a specific area, and that they are "past due enabled". The second makes sure that the customer has not been commented on within the last 27 days. It's grouped by customerid, because that is the number that is associated with each individual customer. When I get the results, everything is right except for the comment column...any ideas?
Join much better to nested query so you use the join instead of nested query
Join increase your speed
this query resolve your problem.
SELECT DISTINCT
customerid,id, customername, user, MAX(date) AS 'maxdate', comment
FROM comments inner join customers on comments.customerid = customers.id
WHERE comments.pastdue='1' AND comments.hubarea='1' AND DATEDIFF(NOW(), comments.date) <= 27
GROUP BY customerid
ORDER BY maxdate
I think this might probably do what you are trying to achieve. If you can execute it and maybe report back if it does or not, i can probably tweak it if needed. Logically, it ' should' work - IF i have understood ur problem correctly :)
SELECT X.customerid, X.maxdate, co.id, c.customername, co.user, co.comment
FROM
(SELECT customerid, MAX(date) AS 'maxdate'
FROM comments cm
INNER JOIN customers cu ON cu.id = cm.customerid
WHERE cu.pastdue='1'
AND cu.hubarea='1'
AND DATEDIFF(NOW(), cm.date) <= 27)
GROUP BY customerid) X
INNER JOIN comments co ON X.customerid = co.customerid and X.maxdate = co.date
INNER JOIN customer c ON X.customerid = c.id
ORDER BY X.maxdate
You need to have subquery for each case.
SELECT a.*
FROM comments a
INNER JOIN
(
SELECT customerID, max(`date`) maxDate
FROM comments
GROUP BY customerID
) b ON a.customerID = b.customerID AND
a.`date` = b.maxDate
INNER JOIN
(
SELECT DISTINCT ID
FROM customers
WHERE pastdue = 1 AND hubarea = 1
) c ON c.ID = a.customerID
LEFT JOIN
(
SELECT DISTINCT customerid
FROM comments
WHERE DATEDIFF(NOW(), date) <= 27
) d ON a.customerID = d.customerID
WHERE d.customerID IS NULL
The first join gets the latest record for each customer.
The second join shows only customers from a specific area, and that they are "past due enabled".
The third join, which uses LEFT JOIN, select all customers that has not been commented on within the last 27 days. In this case,only records without on the list are selected because of the condition d.customerID IS NULL.
But tomake your query shorter, if the customers table has already unique records for customer, then you don't need to have subquery on it.Directly join the table and put the condition on the WHERE clause.
SELECT a.*
FROM comments a
INNER JOIN
(
SELECT customerID, max(`date`) maxDate
FROM comments
GROUP BY customerID
) b ON a.customerID = b.customerID AND
a.`date` = b.maxDate
INNER JOIN customers c
ON c.ID = a.customerID
LEFT JOIN
(
SELECT DISTINCT customerid
FROM comments
WHERE DATEDIFF(NOW(), date) <= 27
) d ON a.customerID = d.customerID
WHERE d.customerID IS NULL AND
c.pastdue = 1 AND
c.hubarea = 1
Two of your table columns are not contained in either an aggregate function or the GROUP BY clause. for example suppose that you have two data rows with the same customer id and same date, but with different comment data. how SQL should aggregate these two rows? :( it will generate an error...
try this
select customerid, id, customername, user,date, comment from(
select customerid, id, customername, user,date, comment,
#rank := IF(#current_customer = id, #rank+ 1, 1),
#current_customer := id
from comments
where customerid IN
(SELECT DISTINCT id FROM customers WHERE pastdue='1' AND hubarea='1')
AND customerid NOT IN
(SELECT DISTINCT customerid FROM comments WHERE DATEDIFF(NOW(), date) <= 27)
order by customerid, maxdate desc
) where rank <= 1