I have something like this:
(SELECT COUNT(*) AS total FROM `transactions` WHERE
`asset`='u_{$user_id}' GROUP BY id)
UNION DISTINCT
(SELECT COUNT(*) AS total FROM transactions tr
INNER JOIN payments pa ON tr.asset = CONCAT('p_', pa.id)
WHERE pa.user_id = '{$user_id}'
GROUP BY tr.id)
It gives 1
Now works like this:
SELECT
(SELECT COUNT(*) FROM `transactions`
WHERE `asset`='u_{$user_id}')
+
(SELECT COUNT(*) FROM transactions tr
INNER JOIN payments pa ON tr.asset = CONCAT('p_', pa.id)
WHERE pa.user_id = '{$user_id}')
It gives 6
But i need to get 5.., sow how to make a right query?
Sure, i can do this by php, but..HOW by sql..?
Really "and" and "or" conditions does not matter, they works correctly, the problem is in counting UNION`ed query. The second query correctly counts summ (1+5), but values intersect queries. The first one gives result of just first subquery. So, i need to unique results before count...
In php, it should look like that: i get transactions id list by inner join with payments, than construct a long query in a loop, to get something like SELECT COUNT(*) FROM transactions WHERE (*what i have now* OR id=$id_1 OR id=$id_2 OR id=$id_3 etc..)
UPD: cutted
RESOLVED!=)
SELECT COUNT(*) FROM(
SELECT tr.* FROM transactions tr
WHERE tr.asset='u_{$user_id}' OR (tr.liability='g' AND tr.l_info='{$user_name}')
UNION SELECT tr.* FROM transactions tr
INNER JOIN payments pa ON tr.asset = CONCAT('p_', pa.id)
WHERE pa.user_id = '{$user_id}' AND pa.status='100')
AS total
AS total is importantly!
I gone through your question, and i think you want to fetch the maximum from the union clause, well i am not aware of the mySql, so i have solved your question in MS-SQL.
Logic:- I have used CTE, and afterwards performed UNION operation and then i have selected MAXIMUM from the two.
WITH COUNTT AS (SELECT 1 AS TEST
UNION
SELECT 5 AS TEST)
SELECT MAX(TEST) FROM COUNTT
And, in place of hardcoded "1" and "5", you can use your count query, i think it is what you are looking for. And, please mark it as an answer.
Related
I have such a query:
SELECT DISTINCT type, (SELECT count(*) FROM ads WHERE ad_type = description_table.type)
as count FROM description_table;
It takes for about 5 minutes to execute. What can be the problem here?
EDIT: Changed the table name from 'desc' to 'description_table' to avoid complication.
You need to join your table description_table with ads table. Try this:
SELECT DISTINCT type, (SELECT count(ads.type) FROM ads join description_table on ads.type = description_table.type)
as count FROM `description_table`;
and instead of counting *, try to count some column like id or type
EDIT:
As per your comment you can try this query:
SELECT a.type, count(d.type) as count
FROM description_table d left join ads a on d.type = a.type
group by d.type;
The concerned schema and query is on SQL fiddle here http://sqlfiddle.com/#!2/312d3/16
The JOIN query below gets the result that I want.
SELECT p.*, payer.username as payer_username, payee.username as
payee_username FROM (`payments_history` p) JOIN (SELECT * FROM users)
AS payer ON `payer`.`user_id` = `p`.`payer_id` JOIN (SELECT * FROM
users) AS payee ON `payee`.`user_id` = `p`.`payee_id` ORDER BY
`p`.`created_timestamp`;
Doing a sum() on the "p.amount" column for all the rows works fine too.
SELECT SUM(p.amount) FROM (`payments_history` p) JOIN (SELECT * FROM
users) AS payer ON `payer`.`user_id` = `p`.`payer_id` JOIN (SELECT *
FROM users) AS payee ON `payee`.`user_id` = `p`.`payee_id` ORDER BY
`p`.`created_timestamp`;
But doing a sum() on the same column for the rows on each page (offset,limit) returns an empty result (I would like to have the total of the "amount" column for the rows on each page).
SELECT SUM(p.amount) FROM (`payments_history` p) JOIN (SELECT * FROM
users) AS payer ON `payer`.`user_id` = `p`.`payer_id` JOIN (SELECT *
FROM users) AS payee ON `payee`.`user_id` = `p`.`payee_id` ORDER BY
`p`.`created_timestamp` limit 0,2;
Also in the sum() query, when the offset starts from anything greater than 0 (try LIMIT 2,2), it returns an empty result.
What am I doing wrong?.
Thank you.
Give this a try:
SELECT SUM(l.amount) FROM (
SELECT p.amount FROM payments_history p
INNER JOIN users payer ON payer.user_id=p.payer_id
INNER JOIN users payee ON payee.user_id=p.payee_id
ORDER BY p.created_timestamp
LIMIT 0,10
) l
I'm not sure if you plan to add other fields to the query, or have further conditions in a WHERE clause, but having those joins in there doesn't seem all that useful right now.
Your question is just a little vague. What will be on the page that you want to have sums on? Is it a report for the specific user? If so, then you can just add a WHERE clause to your query to limit the sum to just that user. Something like:
SELECT SUM(p.amount)
FROM (`payments_history` p)
JOIN (SELECT * FROM users) AS payer ON `payer`.`user_id` = `p`.`payer_id`
JOIN (SELECT * FROM users) AS payee ON `payee`.`user_id` = `p`.`payee_id`
WHERE payer.user_id = [the user id]
ORDER BY `p`.`created_timestamp`;
If that's not what you want, then you may want to clarify the question a little bit. It's unclear.
Question:
Are you trying to get the sum of just one row? (your answer in the comments makes it seem that way) If so, that's just the value in the amount. You can't sum a single value.
i wonder how to using group by but still displaying full data? i just want to group it.
here i give an example of my table :
this is my query :
(SELECT dp.menu_paket,d.id_detail,t.no_meja,m.nama_menu,d.jumlah,t.status,t.nama_pegawai
FROM menu m
join detail_paket dp on dp.menu_paket=m.nama_menu
JOIN detail_transaksi d on m.id_menu = d.id_menu
join transaksi t on t.id_transaksi=d.id_transaksi where t.status='progress' and d.status_menu='progress' group by id_detail)
UNION
(SELECT dp.menu_paket,d.id_detail,t.no_meja,p.nama_paket,d.jumlah,t.status,t.nama_pegawai
FROM paket p
join detail_paket dp on dp.id_paket=p.id_paket
JOIN detail_transaksi d on d.id_paket=p.id_paket
join transaksi t on t.id_transaksi=d.id_transaksi where t.status='progress' and d.status_menu='progress' group by id_detail);
thanks..!
You can apply distinct to avoid same multiple records instead of group by. because group by is used when there is aggregate function is your query.
Distinct retrieves single row instead of multiple rows when two rows are totally same.
Try this
select distinct columnname from table name
union
select distinct columnname1 from table name
I think I see two issues.
1) GROUP BY is generally used when you want to group rows for an aggregate function like SUM. You may be looking for ORDER BY, which controls the order of the rows. You can specify multiple columns for ORDER BY to obtain a "grouping" effect. This is what you want if you just want the rows to be next to each other in the list.
2) UNION, at least in the databases I know of, removes duplicate rows. You want UNION ALL if you want to preserve all rows.
Edit:
In response to the poster's comment, you definitely want ORDER BY and maybe UNION ALL. It should be ORDER BY no_meja, id_transaksi. Try the following query and see if it gives you what you want:
SELECT * FROM
((SELECT dp.menu_paket,d.id_detail,t.no_meja,m.nama_menu,d.jumlah,t.status,t.nama_pegawai
FROM menu m
join detail_paket dp on dp.menu_paket=m.nama_menu
JOIN detail_transaksi d on m.id_menu = d.id_menu
join transaksi t on t.id_transaksi=d.id_transaksi
where t.status='progress' and d.status_menu='progress')
UNION ALL
(SELECT dp.menu_paket,d.id_detail,t.no_meja,p.nama_paket,d.jumlah,t.status,t.nama_pegawai
FROM paket p
join detail_paket dp on dp.id_paket=p.id_paket
JOIN detail_transaksi d on d.id_paket=p.id_paket
join transaksi t on t.id_transaksi=d.id_transaksi
where t.status='progress' and d.status_menu='progress')) x
ORDER BY x.no_meja, x.id_transaksi;
I have these tables and queries as defined in sqlfiddle.
First my problem was to group people showing LEFT JOINed visits rows with the newest year. That I solved using subquery.
Now my problem is that that subquery is not using INDEX defined on visits table. That is causing my query to run nearly indefinitely on tables with approx 15000 rows each.
Here's the query. The goal is to list every person once with his newest (by year) record in visits table.
Unfortunately on large tables it gets real sloooow because it's not using INDEX in subquery.
SELECT *
FROM people
LEFT JOIN (
SELECT *
FROM visits
ORDER BY visits.year DESC
) AS visits
ON people.id = visits.id_people
GROUP BY people.id
Does anyone know how to force MySQL to use INDEX already defined on visits table?
Your query:
SELECT *
FROM people
LEFT JOIN (
SELECT *
FROM visits
ORDER BY visits.year DESC
) AS visits
ON people.id = visits.id_people
GROUP BY people.id;
First, is using non-standard SQL syntax (items appear in the SELECT list that are not part of the GROUP BY clause, are not aggregate functions and do not sepend on the grouping items). This can give indeterminate (semi-random) results.
Second, ( to avoid the indeterminate results) you have added an ORDER BY inside a subquery which (non-standard or not) is not documented anywhere in MySQL documentation that it should work as expected. So, it may be working now but it may not work in the not so distant future, when you upgrade to MySQL version X (where the optimizer will be clever enough to understand that ORDER BY inside a derived table is redundant and can be eliminated).
Try using this query:
SELECT
p.*, v.*
FROM
people AS p
LEFT JOIN
( SELECT
id_people
, MAX(year) AS year
FROM
visits
GROUP BY
id_people
) AS vm
JOIN
visits AS v
ON v.id_people = vm.id_people
AND v.year = vm.year
ON v.id_people = p.id;
The: SQL-fiddle
A compound index on (id_people, year) would help efficiency.
A different approach. It works fine if you limit the persons to a sensible limit (say 30) first and then join to the visits table:
SELECT
p.*, v.*
FROM
( SELECT *
FROM people
ORDER BY name
LIMIT 30
) AS p
LEFT JOIN
visits AS v
ON v.id_people = p.id
AND v.year =
( SELECT
year
FROM
visits
WHERE
id_people = p.id
ORDER BY
year DESC
LIMIT 1
)
ORDER BY name ;
Why do you have a subquery when all you need is a table name for joining?
It is also not obvious to me why your query has a GROUP BY clause in it. GROUP BY is ordinarily used with aggregate functions like MAX or COUNT, but you don't have those.
How about this? It may solve your problem.
SELECT people.id, people.name, MAX(visits.year) year
FROM people
JOIN visits ON people.id = visits.id_people
GROUP BY people.id, people.name
If you need to show the person, the most recent visit, and the note from the most recent visit, you're going to have to explicitly join the visits table again to the summary query (virtual table) like so.
SELECT a.id, a.name, a.year, v.note
FROM (
SELECT people.id, people.name, MAX(visits.year) year
FROM people
JOIN visits ON people.id = visits.id_people
GROUP BY people.id, people.name
)a
JOIN visits v ON (a.id = v.id_people and a.year = v.year)
Go fiddle: http://www.sqlfiddle.com/#!2/d67fc/20/0
If you need to show something for people that have never had a visit, you should try switching the JOIN items in my statement with LEFT JOIN.
As someone else wrote, an ORDER BY clause in a subquery is not standard, and generates unpredictable results. In your case it baffled the optimizer.
Edit: GROUP BY is a big hammer. Don't use it unless you need it. And, don't use it unless you use an aggregate function in the query.
Notice that if you have more than one row in visits for a person and the most recent year, this query will generate multiple rows for that person, one for each visit in that year. If you want just one row per person, and you DON'T need the note for the visit, then the first query will do the trick. If you have more than one visit for a person in a year, and you only need the latest one, you have to identify which row IS the latest one. Usually it will be the one with the highest ID number, but only you know that for sure. I added another person to your fiddle with that situation. http://www.sqlfiddle.com/#!2/4f644/2/0
This is complicated. But: if your visits.id numbers are automatically assigned and they are always in time order, you can simply report the highest visit id, and be guaranteed that you'll have the latest year. This will be a very efficient query.
SELECT p.id, p.name, v.year, v.note
FROM (
SELECT id_people, max(id) id
FROM visits
GROUP BY id_people
)m
JOIN people p ON (p.id = m.id_people)
JOIN visits v ON (m.id = v.id)
http://www.sqlfiddle.com/#!2/4f644/1/0 But this is not the way your example is set up. So you need another way to disambiguate your latest visit, so you just get one row per person. The only trick we have at our disposal is to use the largest id number.
So, we need to get a list of the visit.id numbers that are the latest ones, by this definition, from your tables. This query does that, with a MAX(year)...GROUP BY(id_people) nested inside a MAX(id)...GROUP BY(id_people) query.
SELECT v.id_people,
MAX(v.id) id
FROM (
SELECT id_people,
MAX(year) year
FROM visits
GROUP BY id_people
)p
JOIN visits v ON (p.id_people = v.id_people AND p.year = v.year)
GROUP BY v.id_people
The overall query (http://www.sqlfiddle.com/#!2/c2da2/1/0) is this.
SELECT p.id, p.name, v.year, v.note
FROM (
SELECT v.id_people,
MAX(v.id) id
FROM (
SELECT id_people,
MAX(year) year
FROM visits
GROUP BY id_people
)p
JOIN visits v ON ( p.id_people = v.id_people
AND p.year = v.year)
GROUP BY v.id_people
)m
JOIN people p ON (m.id_people = p.id)
JOIN visits v ON (m.id = v.id)
Disambiguation in SQL is a tricky business to learn, because it takes some time to wrap your head around the idea that there's no inherent order to rows in a DBMS.
im geting this error when trying to do 2 counts inside of my query
first ill show you the query:
$sql = mysql_query("select c.id, c.number, d.name,
(select count(*) from `parts` where `id_container`=c.id group by `id_car`) as packcount,
(select count(*) from `parts` where `id_container`=c.id) as partcount
from `containers` as c
left join `destinations` as d on (d.id = c.id_destination)
order by c.number asc") or die(mysql_error());
now the parts table has 2 fields that i need to use in the count:
id_car
id_container
id_car = the ID of the car the part is for
id_container = the ID of the container the part is in
for packcount all i want is a count of the total cars per container
for partcount all i want it a count of the total parts per container
It's because of GROUP BY You're using
Try something like
(select count(distinct id_car) from `parts` where `id_container`=c.id)
in You're subquery (can't check right now)
EDIT
PFY - I think UNIQUE is for indexes
Your grouping in your first sub-query is causing multiple rows to be returned, you will probably need to run separate queries to get the results you are looking for.
This subquery may return more than one row.
(select count(*) from `parts` where `id_container`=c.id group by `id_car`) as packcount, ...
so, i'd suggest to try something of the following:
(select count(DISTINCT `id_car`) from `parts` where `id_container`=c.id) as packcount, ...
see: COUNT(DISTINCT) on dev.mysql.com
and: QA on stackoverflow