SELECT MAX DATE for each ID - mysql

I have two calls this "tipo_hh" and "tipo_hh_historial".
I need to make a join between the two tables, where "id" is the same in both tables.
But I need that for each "id" in the table "tipo_hh" select the "valor" on the table "tipo_hh_historial" with the condition that is the record with "fecha_cambio" and "hora_cambio" maxima.
"id" is primary key and auto increment in the table "tipo_hh"
Something like this.
This is the table "tipo_hh"
id nombre
1 Reefer
2 Lavados
3 Dry
4 Despacho
This is the table "tipo_hh_historial"
id valor fecha_cambio hora_cambio
1 1.50 27/06/2013 19:15:05
1 5.50 27/06/2013 19:19:32
1 5.50 27/06/2013 19:20:06
1 2.50 27/06/2013 21:03:30
2 4.66 27/06/2013 19:15:17
2 3.00 27/06/2013 19:20:22
3 5.00 27/06/2013 19:20:32
4 1.50 27/06/2013 19:20:50
And I need this:
id nombre valor
1 Reefer 2.50
2 Lavados 3.00
3 Dry 5.00
4 Despacho 1.50

Using a sub query to get the max date / time for the historical record for each id, and using that to get the rest of the latest historical record:-
SELECT tipo_hh.id, tipo_hh.nombre, tipo_hh_historial.valor
FROM tipo_hh
INNER JOIN
(
SELECT id, MAX(STR_TO_DATE(CONCAT(fecha_cambio, hora_cambio), '%d/%m/%Y%k:%i:%s')) AS MaxDateTime
FROM tipo_hh_historial
GROUP BY id
) Sub1
ON tipo_hh.id = Sub1.id
INNER JOIN tipo_hh_historial
ON tipo_hh_historial.id = Sub1.id
AND STR_TO_DATE(CONCAT(fecha_cambio, hora_cambio), '%d/%m/%Y%k:%i:%s') = Sub1.MaxDateTime
SQL Fiddle:-
http://www.sqlfiddle.com/#!2/68baa/2

First of all you should use proper data types for your columns like for date there should a column of type data same as for the time column in you sample data set you have date formatted as '%d/%m/%Y' id this could be change to standard format '%Y-%m-%d' this will be good to so the below query is for proper types for the columns
SELECT t.* ,new_tipo_hh_historial.`valor`
FROM tipo_hh_new t
JOIN (
SELECT th.*
FROM tipo_hh_historial_new th
JOIN (
SELECT id,valor,
MAX(fecha_cambio ) fecha_cambio
,MAX(hora_cambio) hora_cambio
FROM `tipo_hh_historial_new`
GROUP BY id
) thh
ON (
th.`id` =thh.`id`
AND th.fecha_cambio=thh.`fecha_cambio`
AND th.hora_cambio = thh.`hora_cambio`
)
) new_tipo_hh_historial
USING (id)
Fiddle Demo
And for in case you have date and time stored as string then you need to format them as real types you can use below query but not recommended
SELECT t.* ,new_tipo_hh_historial.`valor`
FROM tipo_hh t
JOIN (
SELECT th.*
FROM tipo_hh_historial th
JOIN (
SELECT id,valor,
MAX(STR_TO_DATE(fecha_cambio , '%d/%m/%Y')) fecha_cambio
,MAX(TIME_FORMAT(hora_cambio,'%H:%i:%s')) hora_cambio
FROM `tipo_hh_historial`
GROUP BY id
) thh
ON (
th.`id` =thh.`id`
AND STR_TO_DATE(th.fecha_cambio , '%d/%m/%Y')=thh.`fecha_cambio`
AND TIME_FORMAT(th.hora_cambio,'%H:%i:%s') = thh.`hora_cambio`
)
) new_tipo_hh_historial
USING (id)
Fiddle Demo
Your problem seems like the greatest-n-per-group problem so you can first get the maxima from your table tipo_hh_historial maxima of fecha_cambio and hora_cambio and need to self join with multiple conditions to get the maximums like i.e
ON (
th.`id` =thh.`id`
AND th.fecha_cambio=thh.`fecha_cambio`
AND th.hora_cambio = thh.`hora_cambio`
)
and then join with your first table to get the expected results
Edit: the problem spotted by #Kickstart he already answered so i will provide the another way to overcome.There should be single field to store the date and time for the record like for fecha_cambio DATETIME so there will no chance to miss the id and get the correct maxima for date and time.See below updated query
SELECT t.* ,new_tipo_hh_historial.`valor`
FROM tipo_hh_new t
JOIN (
SELECT th.*
FROM tipo_hh_historial_alter th
JOIN (
SELECT id,valor,
MAX(fecha_cambio ) fecha_cambio
FROM `tipo_hh_historial_alter`
GROUP BY id
) thh
ON (
th.`id` =thh.`id`
AND th.fecha_cambio=thh.`fecha_cambio`
)
) new_tipo_hh_historial
USING (id)
Updated fiddle demo

try this:
SELECT A.id, B.nombre, A.valor, MAX(A.hora_cambio) AS hora_cambio_time
FROM tipo_hh_historial AS A
INNER JOIN tipo_hh AS B
ON(A.id = B.id)
GROUP BY A.id

SELECT tipo_hh.id, tipo_hh.nombre, tipo_hh_historial.valor
FROM tipo_hh INNER JOIN tipo_hh_historial
ON tipo.id = tipo_hh_historial.id AS
group by tipo_hh_historial.id
Having max(tipo_hh_historial.hora_cambio);

Related

How to get MAX date from table join that use UNION?

I have 3 table that need to be joined to get the max date.
table_grade_A
ID_GRADE GRADE NOTE SURVEYOR
1 70.7 PASS TOM
3 51.2 FAIL TOM
table_grade_B
ID_GRADE SUB_GRADE_I SUB_GRADE_II TOTAL_GRADE NOTE SURVEYOR
2 30.8 40.1 70.9 PASS MARVOLO
4 10.3 54.1 64.4 FAIL MARVOLO
5 41.7 20.9 62.6 FAIL RIDDLE
table_grade
ID_GRADE STUDENT TEST_DATE
1 MIYA 2018-12-20
2 LAYLA 2018-12-21
3 MIYA 2018-12-21
4 MIYA 2018-12-22
5 KARRIE 2018-12-28
Every student may get different test and different test stored in different table. I use UNION to populate the value from table_grade_a and table_grade_b and JOIN them to table_grade
My current query:
SELECT tg.STUDENT, MAX(tg.TEST_DATE) AS 'TEST_DATE', temp_grade.* FROM `table_grade` tg
INNER JOIN (
SELECT ID_GRADE,GRADE,NOTE
FROM table_grade_a 'tga'
UNION ALL
SELECT ID_GRADE,TOTAL_GRADE AS GRADE,NOTE
FROM table_grade_a 'tgb'
)temp_grade ON tg.ID_GRADE = temp_grade.ID_GRADE
WHERE tg.STUDENT = 'MIYA'
The result of above query is:
STUDENT TEST_DATE GRADE NOTE
MIYA 2018-12-22 70.7 PASS
The expected output should be:
STUDENT TEST_DATE GRADE NOTE
MIYA 2018-12-22 64.4 FAIL
For a result corresponding the the max date of each student:
The MIN or MAX of a column does not necessarily align to the other values of the wanted row(s), so you need to do more than just calculate the maximum date. In MySQL prior to version 8 you could do something like this, by calculating the maximum dates then using that as an inner join to limit the rows to those corresponding to the maximum values:
select
temp_grade .*
from table_grade tg
inner join (
select student, max(test_date) as test_date
from table_grade
group by student
) gd on tg.student = gd.student and tg.test_date = gd.test_date
INNER JOIN (
SELECT ID_GRADE,GRADE,NOTE
FROM table_grade_a 'tga'
UNION ALL
SELECT ID_GRADE,TOTAL_GRADE AS GRADE,NOTE
FROM table_grade_a 'tgb'
)temp_grade ON tg.ID_GRADE = temp_grade.ID_GRADE
# WHERE tg.STUDENT = 'MIYA'
In MySQL v8+ you could use row_number() over(...) instead:
select
temp_grade .*
from (
select *
, row_number() over(partition by student order by test_date DESC) as rn
from table_grade
) tg
INNER JOIN (
SELECT ID_GRADE,GRADE,NOTE
FROM table_grade_a 'tga'
UNION ALL
SELECT ID_GRADE,TOTAL_GRADE AS GRADE,NOTE
FROM table_grade_a 'tgb'
)temp_grade ON tg.ID_GRADE = temp_grade.ID_GRADE
where tg.rn = 1
# and tg.STUDENT = 'MIYA'
The problem with your current approach is that you are selecting the max date, a table level aggregate, while also asking for all individual records at the same time. This does make sense. One correct possibility would be to use LIMIT with ORDER BY:
SELECT tg1.STUDENT, tg1.TEST_DATE, tg2.*
FROM table_grade tg1
INNER JOIN
(
SELECT ID_GRADE, GRADE, NOTE
FROM table_grade_a
UNION ALL
SELECT ID_GRADE, TOTAL_GRADE, NOTE
FROM table_grade_b
) tg2
ON tg1.ID_GRADE = tg2.ID_GRADE
WHERE
tg1.STUDENT = 'MIYA'
ORDER BY
tg1.TEST_DATE DESC
LIMIT 1;

How to get all entries with SQL query with join

kon
id | name
1 alex
2 peter
3 john
ticket
id | amount | kon_id | package
122 13 1 234
123 12 1 234
124 20 2 NULL
125 23 2 235
126 19 1 236
I would like to get a list of all contacts with the sum of the amount, except tickets, where the package entry is NULL.
My problem is, that I only get the contacts which have a ticket, because of the WHERE clause.
SELECT
kon.id,
kon.name,
SUM(ticket.amount)
FROM kon LEFT JOIN ticket ON kon.id = ticket.kon_id
WHERE ticket.package IS NOT NULL
GROUP BY kon.id
At the moment, the output looks like this
1 alex 44
2 peter 23
but it should look like this
1 alex 44
3 john NULL
2 peter 23
I use a MySQL Server.
Is it possible to solve this?
Replace Where with AND
SELECT
kon.id,
kon.name,
SUM(ticket.amount)
FROM kon LEFT JOIN ticket ON kon.id = ticket.kon_id AND ticket.package IS NOT NULL
GROUP BY kon.id
Check This.
SELECT
k.id,
k.name ,
coalesce (SUM(t.amount) ,0)
FROM kon k LEFT JOIN
( select id,amount,kon_id,package from ticket where package is not null ) t
ON k.id = t.kon_id
GROUP BY k.id, k.name
OutPut :
Begin Tran
Create Table #Kon (id INt , name Nvarchar(255))
Insert into #Kon
Select 1,'alex' UNION ALL
Select 2,'peter' UNION ALL
Select 3,'john'
Create Table #Ticket (id int,amount int,Kon_Id Int,Package Int)
INSERT INTO #Ticket
SELECT 122,13,1,234 UNION ALL
SELECT 123,12,1,234 UNION ALL
SELECT 124,20,2,NULL UNION ALL
SELECT 125,23,2,235 UNION ALL
SELECT 126,19,1,236
SELECT K.id, Name,SUM(amount) amount
FROM #Kon k
LEFT JOIN #Ticket T ON K.id=T.Kon_Id
GROUP BY K.id,Name
RollBAck Tran
Generally, "ticket.package IS NOT NULL" is wrong condition: your query becomes inner join from left join. If ticket.package should be NOT NULL to add from amount, it should be not in condition, but inside SUM agregate function.
working example for MS SQL
SELECT
kon.id,
min(kon.name),
SUM(case when package is NULL then 0 else ticket.amount end)
FROM #kon kon LEFT JOIN #ticket ticket ON kon.id = ticket.kon_id
GROUP BY kon.id
Answer from Mr. Bhosale is right too, but for big tables will have worse performance (the reason is subquery)
the following query return your expected result
SELECT
kon.id,
kon.name,
SUM(ticket.amount) as 'amount'
FROM kon LEFT JOIN ticket ON kon.id = ticket.kon_id
GROUP BY kon.id, kon.name
attached image shows the result
I figured out the fastest way to solve the problem. It takes about 0.2s compared to the other solutions (2s - 2min). The CAST is important, otherwise the summation of double variables is wrong (float string problem).
SELECT
kon1,
kon2,
SUM(CAST(kon3 AS DECIMAL(7,2)))
FROM (
SELECT k.id kon1, k.name kon2, t.amount kon3 FROM kon as k
LEFT JOIN ticket t ON k.id = t.ticket_kon
WHERE t.package IS NOT NULL
UNION ALL
SELECT k.id kon1, k.name kon2, NULL kon3 FROM kon k WHERE) t1
GROUP BY kon1, kon2

I need help regarding JOIN query in mysql

I have started learning MySQL and I'm having a problem with JOIN.
I have two tables: purchase and sales
purchase
--------------
p_id date p_cost p_quantity
---------------------------------------
1 2014-03-21 100 5
2 2014-03-21 20 2
sales
--------------
s_id date s_cost s_quantity
---------------------------------------
1 2014-03-21 90 9
2 2014-03-22 20 2
I want these two tables to be joined where purchase.date=sales.date to get one of the following results:
Option 1:
p_id date p_cost p_quantity s_id date s_cost s_quantity
------------------------------------------------------------------------------
1 2014-03-21 100 5 1 2014-03-21 90 9
2 2014-03-21 20 2 NULL NULL NULL NULL
NULL NULL NULL NULL 2 2014-03-22 20 2
Option 2:
p_id date p_cost p_quantity s_id date s_cost s_quantity
------------------------------------------------------------------------------
1 2014-03-21 100 5 NULL NULL NULL NULL
2 2014-03-21 20 2 1 2014-03-21 90 9
NULL NULL NULL NULL 2 2014-03-22 20 2
the main problem lies in the 2nd row of the first result. I don't want the values
2014-03-21, 90, 9 again in row 2... I want NULL instead.
I don't know whether it is possible to do this. It would be kind enough if anyone helps me out.
I tried using left join
SELECT *
FROM sales
LEFT JOIN purchase ON sales.date = purchase.date
output:
s_id date s_cost s_quantity p_id date p_cost p_quantity
1 2014-03-21 90 9 1 2014-03-21 100 5
1 2014-03-21 90 9 2 2014-03-21 20 2
2 2014-03-22 20 2 NULL NULL NULL NULL
but I want 1st 4 values of 2nd row to be NULL
Since there are no common table expressions or full outer joins to work with, the query will have some duplication and instead need to use a left join unioned with a right join;
SELECT p_id, p.date p_date, p_cost, p_quantity,
s_id, s.date s_date, s_cost, s_quantity
FROM (
SELECT *,(SELECT COUNT(*) FROM purchase p1
WHERE p1.date=p.date AND p1.p_id<p.p_id) rn FROM purchase p
) p LEFT JOIN (
SELECT *,(SELECT COUNT(*) FROM sales s1
WHERE s1.date=s.date AND s1.s_id<s.s_id) rn FROM sales s
) s
ON s.date=p.date AND s.rn=p.rn
UNION
SELECT p_id, p.date p_date, p_cost, p_quantity,
s_id, s.date s_date, s_cost, s_quantity
FROM (
SELECT *,(SELECT COUNT(*) FROM purchase p1
WHERE p1.date=p.date AND p1.p_id<p.p_id) rn FROM purchase p
) p RIGHT JOIN (
SELECT *,(SELECT COUNT(*) FROM sales s1
WHERE s1.date=s.date AND s1.s_id<s.s_id) rn FROM sales s
) s
ON s.date=p.date AND s.rn=p.rn
An SQLfiddle to test with.
In a general sense, what you're looking for is called a FULL OUTER JOIN, which is not directly available in MySQL. Instead you only get LEFT JOIN and RIGHT JOIN, which you can UNION together to get essentially the same result. For a very thorough discussion on this subject, see Full Outer Join in MySQL.
If you need help understanding the different ways to JOIN a table, I recommend A Visual Explanation of SQL Joins.
The way this is different from a regular FULL OUTER JOIN is that you're only including any particular row from either table at most once in the JOIN result. The problem being, if you have one purchase record and two sales records on a particular day, which sales record is the purchase record associated with? What is the relationship you're trying to represent between these two tables?
It doesn't sound like there's any particular relationship between purchase and sales records, except that some of them happened to take place on the same day. In which case, you're using the wrong tool for the job. If all you want to do is display these tables side by side and line the rows up by date, you don't need a JOIN at all. Instead, you should SELECT each table separately and do your formatting with some other tool (or manually).
Here's another way to get the same result, but the EXPLAIN for this is horrendous; and performance with large sets is going to be atrocious.
This is essentially two queries UNIONed together. The first query is essentially "purchase LEFT JOIN sales", the second query is essentially "sales ANTI JOIN purchase".
Because there is no foreign key relationship between the two tables, other than rows matching on date, we have to "invent" a key we can join on; we use user variables to assign ascending integer values to each row within a given date, so we can match row 1 from purchase to row 1 from sales, etc.
I wouldn't normally generate this type of result using SQL; it's not a typical JOIN operation, in the sense of how we traditionally join tables.
But, if I had to produce the specified resultset using MySQL, I would do it like this:
SELECT p.p_id
, p.p_date
, p.p_cost
, p.p_quantity
, s.s_id
, s.s_date
, s.s_cost
, s.s_quantity
FROM ( SELECT #pl_i := IF(pl.date = #pl_prev_date,#pl_i+1,1) AS i
, #pl_prev_date := pl.date AS p_date
, pl.p_id
, pl.p_cost
, pl.p_quantity
FROM purchase pl
JOIN ( SELECT #pl_i := 0, #pl_prev_date := NULL ) pld
ORDER BY pl.date, pl.p_id
) p
LEFT
JOIN ( SELECT #sr_i := IF(sr.date = #sr_prev_date,#sr_i+1,1) AS i
, #sr_prev_date := sr.date AS s_date
, sr.s_id
, sr.s_cost
, sr.s_quantity
FROM sales sr
JOIN ( SELECT #sr_i := 0, #sr_prev_date := NULL ) srd
ORDER BY sr.date, sr.s_id
) s
ON s.s_date = p.p_date
AND s.i = p.i
UNION ALL
SELECT p.p_id
, p.p_date
, p.p_cost
, p.p_quantity
, s.s_id
, s.s_date
, s.s_cost
, s.s_quantity
FROM ( SELECT #sl_i := IF(sl.date = #sl_prev_date,#sl_i+1,1) AS i
, #sl_prev_date := sl.date AS s_date
, sl.s_id
, sl.s_cost
, sl.s_quantity
FROM sales sl
JOIN ( SELECT #sl_i := 0, #sl_prev_date := NULL ) sld
ORDER BY sl.date, sl.s_id
) s
LEFT
JOIN ( SELECT #pr_i := IF(pr.date = #pr_prev_date,#pr_i+1,1) AS i
, #pr_prev_date := pr.date AS p_date
, pr.p_id
, pr.p_cost
, pr.p_quantity
FROM purchase pr
JOIN ( SELECT #pr_i := 0, #pr_prev_date := NULL ) prd
ORDER BY pr.date, pr.p_id
) p
ON p.p_date = s.s_date
AND p.i = s.i
WHERE p.p_date IS NULL
ORDER BY COALESCE(p_date,s_date),COALESCE(p_id,s_id)

Identifying groups in Group By

I am running a complicated group by statement and I get all my results in their respective groups. But I want to create a custom column with their "group id". Essentially all the items that are grouped together would share an ID.
This is what I get:
partID | Description
-------+---------+--
11000 | "Oven"
12000 | "Oven"
13000 | "Stove"
13020 | "Stove"
12012 | "Grill"
This is what I want:
partID | Description | GroupID
-------+-------------+----------
11000 | "Oven" | 1
12000 | "Oven" | 1
13000 | "Stove" | 2
13020 | "Stove" | 2
12012 | "Grill" | 3
"GroupID" does not exist as data in any of the tables, it would be a custom generated column (alias) that would be associated to that group's key,id,index, whatever it would be called.
How would I go about doing this?
I think this is the query that returns the five rows:
select partId, Description
from part p;
Here is one way (using standard SQL) to get the groups:
select partId, Description,
(select count(distinct Description)
from part p2
where p2.Description <= p.Description
) as GroupId
from part p;
This is using a correlated subquery. The subquery is finding all the description values less than the current one -- and counting the distinct values. Note that this gives a different set of values from the ones in the OP. These will be alphabetically assigned rather than assigned by first encounter in the data. If that is important, the OP should add that into the question. Based on the question, the particular ordering did not seem important.
Here's one way to get it:
SELECT p.partID,p.Description,b.groupID
FROM (
SELECT Description,#rn := #rn + 1 AS groupID
FROM (
SELECT distinct description
FROM part,(SELECT #rn:= 0) c
) a
) b
INNER JOIN part p ON p.description = b.description;
sqlfiddle demo
This gets assigns a diferent groupID to each description, and then joins the original table by that description.
Based on your comments in response to Gordon's answer, I think what you need is a derived table to generate your groupids, like so:
select
t1.description,
#cntr := #cntr + 1 as GroupID
FROM
(select distinct table1.description from table1) t1
cross join
(select #cntr:=0) t2
which will give you:
DESCRIPTION GROUPID
Oven 1
Stove 2
Grill 3
Then you can use that in your original query, joining on description:
select
t1.partid,
t1.description,
t2.GroupID
from
table1 t1
inner join
(
select
t1.description,
#cntr := #cntr + 1 as GroupID
FROM
(select distinct table1.description from table1) t1
cross join
(select #cntr:=0) t2
) t2
on t1.description = t2.description
SQL Fiddle
SELECT partID , Description, #s:=#s+1 GroupID
FROM part, (SELECT #s:= 0) AS s
GROUP BY Description

Select Count of Rows with Joined Tables

I have two tables with a one to many relationship. I join the tables by an id column. My problem is that I need a count of all matching entries from the second (tablekey_id) table but I need the information from the row marked with the boolean is_basedomain. As a note there is only one row with is_basedomain = 1 per set of rows with the same tablekey_id.
Table: tablekey
id linkdata_id timestamp
22 9495028175 2013-03-10 01:13:46
23 8392740179 2013-03-10 21:23:25
Table: searched_domains.
NOTE: tablekey_id is the foreign key to the id in the tablekey table.
id tablekey_id domain is_basedomain
1 22 somesite.com 1
2 22 yahoo.com 0
3 23 red.com 1
4 23 blue.com 0
5 23 green.com 0
Heres the query Im working with. I was trying to use a sub query but I cant seem to select only the count for the current tablekey_id so this does not work.
SELECT `tablekey_id`, `linkdata_id`, `timestamp`, `domain`, `is_basedomain`,
(SELECT COUNT(1) AS other FROM `searched_domains` AS dd
ON dd.tablekey_id = d.tablekey_id GROUP BY `tablekey_id`) AS count
FROM `tablekey` AS k
JOIN `searched_domains` AS d
ON k.id = d.tablekey_id
WHERE `is_basedomain` = 1 GROUP BY `tablekey_id`
The result that I would like to get back is:
tablekey_id linkdata_id timestamp domain is_basedomain count
22 9495028175 2013-03-10 01:13:46 somesite.com 1 2
23 8392740179 2013-03-10 21:23:25 red.com 1 3
Can anyone help me get this into one query?
You can treat the searched_domains rows that have is_basedomain=1 as a separate table in the query and join it with another instance of searched_domains (to get the count):
SELECT
d.tablekey_id,
k.linkdata_id,
k.timestamp,
d.domain,
d.is_basedomain,
COUNT(*) as 'count'
FROM
tablekey AS k
join searched_domains AS d on d.tablekey_id=k.id
join searched_domains AS d2 on d2.tablekey_id=d.tablekey_id
WHERE
d.is_basedomain = 1
GROUP BY
d.tablekey_id,
k.linkdata_id,
k.timestamp,
d.domain,
d.is_basedomain
you have an error when using ON instead use WHERE
try this
SELECT `tablekey_id`, `linkdata_id`, `timestamp`, `domain`, `is_basedomain`,
(SELECT COUNT(1) AS other FROM `searched_domains` AS dd
where dd.tablekey_id = d.tablekey_id GROUP BY `tablekey_id`) AS count
FROM `tablekey` AS k
JOIN `searched_domains` AS d
ON k.id = d.tablekey_id
WHERE `is_basedomain` = 1 GROUP BY `tablekey_id`
DEMO HERE
There is no reason to use subquery, or what is your opinion?
SELECT
`tablekey_id`,
`linkdata_id`,
`timestamp`,
`domain`,
`is_basedomain`,
COUNT(*) as count
FROM
`tablekey` AS k ,
`searched_domains` AS d
WHERE
k.id = d.tablekey_id AND
`is_basedomain` = 1
GROUP BY
`tablekey_id`,
`linkdata_id`,
`timestamp`,
`domain`,
`is_basedomain`
If you want only latest timestamp use MAX(timestamp) as timestamp and remove it from group by.