I have a table that has some values in it, along with the time that value was taken against an associated ID from another table.
I am looking to retrieve the latest value for every item in that table, and then order by those latest values.
Here is an SQL fiddle, http://www.sqlfiddle.com/#!2/0be99
And here is text output.
'hist' table
| HIST_ID | HIST_ITEM_ID | HIST_VALUE | HIST_TIME |
|---------|--------------|------------|------------|
| 1 | 1 | 1 | 1420291000 |
| 2 | 1 | 2 | 1420292000 |
| 3 | 1 | 3 | 1420293000 |
| 4 | 1 | 5 | 1420294000 |
| 5 | 1 | 10 | 1420295000 |
| 6 | 1 | 50 | 1420296000 |
| 7 | 1 | 60 | 1420297000 |
| 8 | 1 | 77 | 1420298000 |
| 9 | 1 | 90 | 1420299000 |
| 10 | 1 | 101 | 1420300000 |
| 11 | 2 | 1 | 1420291000 |
| 12 | 2 | 3 | 1420292000 |
| 13 | 2 | 7 | 1420293000 |
| 14 | 2 | 9 | 1420294000 |
| 15 | 2 | 15 | 1420295000 |
| 16 | 2 | 21 | 1420296000 |
| 17 | 2 | 33 | 1420297000 |
| 18 | 2 | 35 | 1420298000 |
| 19 | 2 | 55 | 1420299000 |
| 20 | 2 | 91 | 1420300000 |
'items' table
| ITEM_ID | ITEM_TITLE |
|---------|------------|
| 1 | ABCD |
| 2 | XYZ123 |
So, I can do something like...
select * from hist
inner join items on hist_item_id = item_id
group by hist_item_id
order by hist_value desc
However this returns me a grouping that I cannot order. How can I order this grouping? I had a look at other similar questions on here but was unable to apply their solutions successfully to my query to produce the desire result.
The desired result here would be to return.
HIST_ITEM_ID | ITEM_TITLE | HIST_VALUE |
|------------|------------|------------|
| 1 | ABCD | 101 |
| 2 | XYZ123 | 91 |
You can use a join to get the most recent history item. Then you can join back to the history table and the item table to get additional information:
select h.*, i.item_title
from (select hist_item_id, max(hist_id) as max_hist_id
from hist
group by hist_item_id
) hh join
hist h
on h.hist_id = hh.max_hist_id join
items i
on i.item_id = hh.hist_item_id;
Here is a SQL Fiddle.
You should use MAX function and group by the item id. That would look like this:
SELECT i.item_id, i.item_title, MAX(h.hist_value)
FROM items AS i
INNER JOIN hist AS h
ON i.item_id = h.hist_item_id
GROUP BY i.item_id
Related
I'll get straight to the point.
I've 2 tabels:
1) poll_options
| (ID) | Name |
| 1 | 0-5 |
| 2 | 5-10 |
| 3 | 10-15 |
| 4 | 15-20 |
| 5 | 20-25 |
| 6 | 25-30 |
| 7 | 30-35 |
| 8 | 35-40 |
| 9 | 40-45 |
| 10 | 45-50 |
| 11 | 50+ |
2) poll_votes
| ID | (poll_options_id) | vote_count | woning_id |
| 1 | 3 | 1 | 20 |
| 2 | 11 | 1 | 18 |
| 3 | 5 | 1 | 25 |
| 4 | 5 | 1 | 27 |
| 5 | 3 | 1 | 25 |
| 6 | 4 | 1 | 26 |
Linking them together is the ID from poll_options with poll_options_ID from poll_votes. I placed ( ) around them to make is visual.
I've made a query to show the total votes made for each answer.
SELECT o.name as answer, sum(v.vote_count) as total_votes_per_answer
FROM poll_options as o LEFT JOIN poll_votes as v ON v.poll_option_id = o.id
WHERE WONING_id='$woning_id'
GROUP BY o.name
ORDER BY o.id ASC
Here is where my problem is.
It only shows the name from poll_options that have a vote.
I would like to show all the name of poll_options and the ones where there is no vote yet, make them show 0.
for example (with current sql and woning_id=20):
| answer |total_votes_per_answer|
| 0-5 | 1 |
| 5-10 | 1 |
What I want it to be:
| answer |total_votes_per_answer|
| 0-5 | 1 |
| 5-10 | 1 |
| 10-15 | 0 |
| 15-20 | 0 |
| 20-25 | 0 |
| 25-30 | 0 |
| 30-35 | 0 |
| 35-40 | 0 |
| 40-45 | 0 |
| 45-50 | 0 |
| 50+ | 0 |
Is there something in SQL that I can use to get this result?
Your SQL is invalid, but it would work if you inserted and:
SELECT o.name as answer, sum(v.vote_count) as total_votes_per_answer
FROM poll_options o LEFT JOIN
poll_votes v
ON v.poll_option_id = o.id AND WONING_id = '$woning_id'
GROUP BY o.name
ORDER BY o.id ASC;
That said, you should be passing $woning_id as a parameter into the query. Don't munge query strings with such values -- they can cause unexpected and hard to find errors.
How to get count of combinations from database?
I have to database tables and want to get the count of combinations. Does anybody know how to put this in a database query, therefore I haven't a db request for each trip?
Trips
| ID | Driver | Date |
|----|--------|------------|
| 1 | A | 2015-12-15 |
| 2 | A | 2015-12-16 |
| 3 | B | 2015-12-17 |
| 4 | A | 2015-12-18 |
| 5 | A | 2015-12-19 |
Passengers
| ID | PassengerID | TripID |
|----|-------------|--------|
| 1 | B | 1 |
| 2 | C | 1 |
| 3 | D | 1 |
| 4 | B | 2 |
| 5 | D | 2 |
| 6 | A | 3 |
| 7 | B | 4 |
| 8 | D | 4 |
| 9 | B | 5 |
| 10 | C | 5 |
Expected result
| Driver | B-C-D | B-D | A | B-C |
|--------|-------|-----|---|-----|
| A | 1 | 2 | - | 1 |
| B | - | - | 1 | - |
Alternative
| Driver | Passengers | Count |
|--------|------------|-------|
| A | B-C-D | 1 |
| A | B-D | 2 |
| A | B-C | 1 |
| B | A | 1 |
Has anybody an idea?
Thanks a lot!
Try this:
SELECT Driver, Passengers, COUNT(*) AS `Count`
FROM (
SELECT t.ID, t.Driver,
GROUP_CONCAT(p.PassengerID
ORDER BY p.PassengerID
SEPARATOR '-') AS Passengers
FROM Trips AS t
INNER JOIN Passengers AS p ON t.ID = p.TripID
GROUP BY t.ID, t.Driver) AS t
GROUP BY Driver, Passengers
The above query will produce the alternative result set. The other result set can only be achieved using dynamic sql.
Demo here
i want to find solution for my query problem. I need to find the SUM of all priceProduct*quantity and separated with each of productcategory. I have already made a query, but it takes longer time to executed it. this is my query,
SELECT
pb.ProductCategoryID,
pb.ProductCategoryDescription,
(SELECT
SUM((SELECT pd.HPP FROM `price details` pd WHERE pd.ProductID = pdt.ProductID ORDER BY pd.PriceDetailID DESC LIMIT 1)*
(SELECT StockProductBallance FROM `stock product` sp WHERE sp.ProductID = pdt.ProductID ORDER BY sp.StockProductID DESC LIMIT 1))
FROM product pdt
WHERE pdt.ProductCategoryID = pb.ProductCategoryID
) AS Total
FROM `product category` pb
GROUP BY pb.ProductCategoryID
this my example table
table product:
+------+-------+
| id_p | id_pc |
+------+-------+
| 1 | 3 |
| 2 | 4 |
| 3 | 3 |
| 4 | 4 |
+------+-------+
table productcategory:
+-------+---------+
| id_pc | pc_name |
+-------+---------+
| 3 | new_pc |
| 4 | old_pc |
+-------+---------+
table price details:
+---------------+------+-----+
| PriceDetailID | id_p | hpp |
+---------------+------+-----+
| 1 | 1 | 100 |
| 2 | 1 | 110 |
| 3 | 1 | 120 |
| 4 | 2 | 200 |
| 5 | 2 | 210 |
| 6 | 2 | 220 |
+---------------+------+-----+
table stockProduct:
+-----------------+------+---------------+
| id_stockProduct | id_p | stockballance |
+-----------------+------+---------------+
| 1 | 1 | 10 |
| 2 | 1 | 11 |
| 3 | 1 | 12 |
| 4 | 2 | 20 |
| 5 | 2 | 21 |
| 6 | 2 | 22 |
+-----------------+------+---------------+
Really need your help guys, for better query..
I've tried the following queries but unfortunately they don't work :(.
Worth mentioning that each customer has more than one CustomerUsers
select (a.TotalJobs / b.DaysActive) from
(select count(jr.id) as TotalJobs
from jobrequests jr, customers c, customerusers cu
where jr.customeruserid=cu.id
and cu.customerid=c.id
group by c.name) as a,
(select datediff(curdate(), from_unixtime(c.CreationTime)) as DaysActive
from customers c
group by c.name) as b
Please see below the tables
Jobs:
+----+--------------+
| ID | JobRequestID |
+----+--------------+
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 2 |
| 7 | 2 |
| 8 | 3 |
| 9 | 3 |
| 10 | 3 |
| 11 | 4 |
| 12 | 4 |
| 13 | 5 |
| 14 | 5 |
| 15 | 6 |
| 16 | 7 |
| 17 | 8 |
| 18 | 8 |
| 19 | 9 |
| 20 | 10 |
+----+--------------+
JobRequests:
+----+---------------+
| ID | CustomeUserID |
+----+---------------+
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 2 |
| 6 | 3 |
| 7 | 4 |
| 8 | 4 |
| 9 | 4 |
| 10 | 5 |
| 11 | 5 |
| 12 | 5 |
| 13 | 6 |
| 14 | 6 |
| 15 | 7 |
+----+---------------+
CustomerUsers:
+----+------------+
| ID | CustomerID |
+----+------------+
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 2 |
| 7 | 2 |
| 8 | 3 |
| 9 | 3 |
| 10 | 4 |
+----+------------+
Customers:
+----+------+--------------+
| ID | Name | CreationTime |
+----+------+--------------+
| 1 | a | 1415814194 |
| 2 | b | 1415814194 |
| 3 | c | 1415986994 |
| 4 | d | 1415986994 |
+----+------+--------------+
For the moment it returns 16 results (4X4), dividing each result from 1st sub-query to each result from the 2nd one (each of these sub-queries return 4 results). Can anyone please help me to get this to divide only 1 result from sub-query 1 to it's corespondent from sub-query 2?
Thank you in advance.
I suspect that you can do what you want this a query like this:
select c.name, count(*) / (datediff(curdate(), from_unixtime(c.CreationTime))
from customerusers cu join
jobrequests jr
on jr.customeruserid = cu.id join
customers c
on cu.customerid = c.id
group by c.name;
I don't see why you need two subqueries for this.
I'm guessing you need to join your results together -- as currently written, you're producing a cartesian product.
Try something like this adding c.id to each subquery (it's better to group by it presumably rather than the name):
select (a.TotalJobs / b.DaysActive)
from (
select c.id,
count(jr.id) as TotalJobs
from jobrequests jr
join customers c on jr.customeruserid=cu.id
join customerusers cu on cu.customerid=c.id
group by c.id) a join (
select c.id,
datediff(curdate(), from_unixtime(c.CreationTime)) as DaysActive
from customers c
group by c.id) b on a.id = b.id
Please note, I've updated your syntax to use the more standard join syntax.
i have a table called rc_language_type_table with:
id language
1 english
2 Xhosa
3 afrikaans
etc
then i have a table rc_language_type_assoc_table with:
profile_id | language_type_id |
+------------+------------------+
| 3 | 1 |
| 13 | 1 |
| 15 | 1 |
| 16 | 1 |
where i have profiles and each profile is connected to a language id in a 1 to many
so then i did:
select *,count(*) from rc_language_type_assoc_table group by language_type_id;
+------------+------------------+----------+
| profile_id | language_type_id | count(*) |
+------------+------------------+----------+
| 3 | 1 | 96 |
| 3 | 2 | 19 |
| 3 | 3 | 18 |
| 64 | 4 | 51 |
| 94 | 5 | 10 |
| 37 | 6 | 26 |
| 3 | 7 | 21 |
| 3 | 8 | 4 |
| 3 | 9 | 6 |
| 88 | 10 | 4 |
| 3 | 11 | 3 |
+------------+------------------+----------+
what i want now is: instead having the language_type_id i want to display the actual language...how would i do this please???
i tried:
select *, count(*)
from rc_language_type_assoc_table, rc_language_type_table
group by language_type_id
where rc_language_type_assoc_table.language_type_id = rc_language_type_table.id;
but i get a syntax error...
please help??
thank you
GROUP BY should be "after" the WHERE statement and not before
select *, count(*)
from rc_language_type_assoc_table, rc_language_type_table
where rc_language_type_assoc_table.language_type_id = rc_language_type_table.id
group by language_type_id ;