I have 2 tables bellow
0 --> Pending
1 --> Success
2 --> Fail
table : mntnc
+-------+-------+-------+
| id | own | sts |
+-------+-------+-------+
| 1 | BN | 1 |
| 2 | BB | 2 |
| 3 | BN | 1 |
| 4 | BD | 1 |
| 5 | BD | 0 |
table : istlsi
+-------+-------+-------+
| id | own | sts |
+-------+-------+-------+
| 1 | BN | 1 |
| 2 | BB | 1 |
| 3 | BB | 1 |
| 4 | BC | 0 |
| 5 | BD | 2 |
of the two tables above, I want to add both of them to be the table below
+-------+-----------+-----------+-----------+
| own | success | fail | pending |
+-------+-----------+-----------+-----------+
| BN | 3 | 0 | 0 |
| BB | 2 | 1 | 0 |
| BD | 1 | 1 | 1 |
| BC | 0 | 0 | 1 |
The two key points here:
Union tables (I aliased result to B)
Use sum(case...) for each column.
First we union both tables together as an inline view.
We then use a case statement for each desired column and evaluate the status setting the value to 1 or 0 depending on sts value. and then sum those...
SELECT own
, sum(case when sts=1 then 1 else 0 end) as Success
, sum(case when sts=2 then 1 else 0 end) as Fail
, sum(case when sts=0 then 1 else 0 end) as Pending
FROM ( SELECT ID, own, sts
FROM mntnc
UNION ALL
SELECT id, own, sts
FROM istlsi
) B
GROUP BY own
Related
I am setting up a virtual classroom in PHP and MySQL. This classroom consists of courses and each course contains different subjects or modules. The student has to examine each module and, finally, a summary (evaluation board) is made to know if the student has passed the course or not.
Having said that, I have a table in which I store the evaluations of each student, in which I keep inscripcion_id (student - inscription_id), modulo_id (module_id), fecha (date_of_examination), aciertos (number_of_right_answers), ultima_convocatoria (evaluation_last_convocatory) and estado (status).
SQL Fiddle -> here
Through some previously established rules that tell me if a student has passed a module or not, I get the following set of data:
+----------------+-----------+---------------------+----------+---------------------+--------+------------+
| inscripcion_id | modulo_id | fecha | aciertos | ultima_convocatoria | estado | ev |
+----------------+-----------+---------------------+----------+---------------------+--------+------------+
| 890 | 1 | 2018-01-24 22:26:09 | 8 | 2 | 1 | aprobado |
| 890 | 2 | 2018-01-24 22:36:58 | 3 | 3 | 0 | suspendido |
| 890 | 5 | 2018-01-24 22:38:50 | 3 | 1 | 0 | suspendido |
| 890 | 6 | 2018-01-24 22:44:20 | 7 | 3 | 0 | suspendido |
| 891 | 1 | 2018-01-25 09:24:42 | 8 | 1 | 1 | aprobado |
| 891 | 2 | 2018-01-25 10:01:55 | 4 | 8 | 0 | suspendido |
| 891 | 4 | 2018-01-25 10:51:49 | 5 | 3 | 1 | suspendido |
| 891 | 5 | 2018-01-25 10:23:45 | 9 | 1 | 1 | aprobado |
| 891 | 6 | 2018-01-25 11:21:20 | 7 | 3 | 0 | suspendido |
| 896 | 1 | 2018-01-25 11:55:48 | 1 | 1 | 1 | suspendido |
| 898 | 1 | 2018-01-25 14:01:51 | 6 | 1 | 1 | suspendido |
| 907 | 1 | 2018-03-25 16:06:18 | 3 | 1 | 0 | suspendido |
| 907 | 2 | 2018-03-25 16:07:34 | 3 | 1 | 0 | suspendido |
| 907 | 3 | 2018-03-25 16:09:04 | 3 | 1 | 0 | suspendido |
| 907 | 4 | 2018-03-25 16:08:13 | 3 | 1 | 0 | suspendido |
| 907 | 5 | 2018-03-25 16:10:37 | 2 | 1 | 0 | suspendido |
| 907 | 6 | 2018-03-25 16:08:44 | 3 | 1 | 0 | suspendido |
+----------------+-----------+---------------------+----------+---------------------+--------+------------+
This data is obtained through the following query:
SELECT e1.inscripcion_id,
e1.modulo_id,
e1.fecha,
e1.aciertos,
e1.convocatoria AS ultima_convocatoria,
e1.estado,
if (
( e1.modulo_id in (SELECT modulo.modulo_id FROM modulo WHERE modulo.curso_id = 1 AND modulo.categoria_id = 1)
AND e1.aciertos <= 7 )
OR ( e1.modulo_id = (SELECT modulo.modulo_id FROM modulo WHERE modulo.curso_id = 1 AND modulo.categoria_id = 2)
AND e1.aciertos <= 11 ),
"suspendido",
"aprobado"
) AS ev
FROM (
SELECT inscripcion_id,
modulo_id,
MAX(convocatoria) AS max_convocatoria
FROM `evaluacion`
GROUP BY inscripcion_id,
modulo_id
ORDER BY `inscripcion_id` ASC,
`modulo_id` ASC,
`convocatoria` ASC
) AS e2
INNER JOIN evaluacion AS e1
ON e1.inscripcion_id = e2.inscripcion_id
AND e1.modulo_id = e2.modulo_id
AND e1.convocatoria = e2.max_convocatoria
As you can see, the student 890, has made modules 1, 2, 5 and 6. What I want to achieve is that the modules that are still pending, I also get as a result in the previous data set. The exemplification:
+----------------+-----------+---------------------+----------+---------------------+--------+------------+
| inscripcion_id | modulo_id | fecha | aciertos | ultima_convocatoria | estado | ev |
+----------------+-----------+---------------------+----------+---------------------+--------+------------+
| 890 | 1 | 2018-01-24 22:26:09 | 8 | 2 | 1 | aprobado |
| 890 | 2 | 2018-01-24 22:36:58 | 3 | 3 | 0 | suspendido |
| 890 | 3 | NULL | NULL | NULL | NULL | pendiente |
| 890 | 4 | NULL | NULL | NULL | NULL | pendiente |
| 890 | 5 | 2018-01-24 22:38:50 | 3 | 1 | 0 | suspendido |
| 890 | 6 | 2018-01-24 22:44:20 | 7 | 3 | 0 | suspendido |
| 891 | 1 | 2018-01-25 09:24:42 | 8 | 1 | 1 | aprobado |
| 891 | 2 | 2018-01-25 10:01:55 | 4 | 8 | 0 | suspendido |
| 891 | 3 | NULL | NULL | NULL | NULL | pendiente |
| 891 | 4 | 2018-01-25 10:51:49 | 5 | 3 | 1 | suspendido |
| 891 | 5 | 2018-01-25 10:23:45 | 9 | 1 | 1 | aprobado |
| 891 | 6 | 2018-01-25 11:21:20 | 7 | 3 | 0 | suspendido |
| 896 | 1 | 2018-01-25 11:55:48 | 1 | 1 | 1 | suspendido |
| 896 | 2 | NULL | NULL | NULL | NULL | pendiente |
| 896 | 3 | NULL | NULL | NULL | NULL | pendiente |
| 896 | 4 | NULL | NULL | NULL | NULL | pendiente |
| 896 | 5 | NULL | NULL | NULL | NULL | pendiente |
| 896 | 6 | NULL | NULL | NULL | NULL | pendiente |
| ... | | | | | | |
+----------------+-----------+---------------------+----------+---------------------+--------+------------+
The result is that the modules that the student has not yet done have been added, with the new value "pending" for the ev column.
I have no idea how to do this ... I've tried, I searched the internet and nothing :(
What is the final objective? What I want is to obtain a final list with all those students who have the pending course (that is, they have some pending module/s), to send them a reminder email that they have to examine themselves of the remaining modules. To those who have approved or suspended, no email will be sent to them.
Can you help me?
SQL Fiddle -> here
THANK YOU VERY MUCH
Suppose you want to get students with no module in evaluation table as 'pending' like what you provided in the example. The way to get student joining all module is to do a full join on modulo and evaluacion to get full set of distinct inscripcion_id modulo_id. Then left join with your existing query will provide the result you want.
sqlfiddle
SELECT fs.inscripcion_id,
fs.modulo_id,
e3.fecha,
e3.aciertos,
e3.ultima_convocatoria,
e3.estado,
IF(e3.ev IS NULL, "pendiente", e3.ev) AS ev
FROM (SELECT m.modulo_id,
e.inscripcion_id
FROM modulo m,
evaluacion e
GROUP BY m.modulo_id,
e.inscripcion_id) AS fs
LEFT JOIN (SELECT
e1.inscripcion_id,
e1.modulo_id,
e1.fecha,
e1.aciertos,
e1.convocatoria
AS
ultima_convocatoria
,
e1.estado,
IF (( e1.modulo_id IN (SELECT modulo.modulo_id
FROM modulo
WHERE modulo.curso_id = 1
AND modulo.categoria_id =
1)
AND e1.aciertos <= 7 )
OR ( e1.modulo_id = (SELECT modulo.modulo_id
FROM modulo
WHERE
modulo.curso_id = 1
AND modulo.categoria_id = 2)
AND e1.aciertos <= 11 ), "suspendido",
"aprobado")
AS ev
FROM (SELECT inscripcion_id,
modulo_id,
Max(convocatoria) AS max_convocatoria
FROM `evaluacion`
GROUP BY inscripcion_id,
modulo_id
ORDER BY `inscripcion_id` ASC,
`modulo_id` ASC,
`convocatoria` ASC) AS e2
INNER JOIN evaluacion AS e1
ON e1.inscripcion_id = e2.inscripcion_id
AND e1.modulo_id = e2.modulo_id
AND e1.convocatoria = e2.max_convocatoria)
AS e3
ON fs.modulo_id = e3.modulo_id
AND fs.inscripcion_id = e3.inscripcion_id
ORDER BY fs.inscripcion_id,
fs.modulo_id;
For the further question,
You may want to use
SELECT inscripcion_id,
SUM(case when ev = 'aprobado' then 1 else 0 end) as approved_cnt,
SUM(case when ev = 'suspendido' then 1 else 0 end) as suspended_cnt,
SUM(case when ev = 'pendiente' then 1 else 0 end) as pending_cnt
From --the above query...
Group by inscripcion_id
to get the count of status for each student, and then do the logic using those count.
After reviewing the new sqlfiddle
I wrote the query below, I think it should cover what you want
Notice that you more than one evaluation per module, meaning that you'll get more than one status per module
To solve that, you can add a group statement (in comment now)
Or you the different evaluations to your needs...
SELECT
i.inscripcion_id,
c.curso_id,
c.titulo AS curso_titulo,
m.modulo_id,
m.titulo AS modulo_titulo,
IFNULL(ev.estado,0) AS estado,
m.*
FROM
inscripcion i
INNER JOIN curso c ON c.curso_id = i.curso_id
INNER JOIN modulo m ON m.curso_id = c.curso_id
LEFT JOIN evaluacion ev ON ev.modulo_id = m.modulo_id
WHERE
(ev.estado = 0 OR ev.estado IS NULL)
/*
GROUP BY
m.modulo_id
*/
;
Presume first, that the following table exists in a MySQL Database
|----|-----|-----|----|----|-----------|--------------|----|
| id | rid | ver | n1 | n2 | s1 | s2 | b1 |
|----|-----|-----|----|----|-----------|--------------|----|
| 1 | 1 | 1 | 0 | 1 | Hello | World | 0 |
| 2 | 1 | 2 | 1 | 1 | Hello | World | 0 |
| 3 | 1 | 3 | 0 | 0 | Goodbye | Cruel World | 0 |
| 4 | 2 | 1 | 0 | 0 | Hello | Doctor | 1 |
| 5 | 2 | 2 | 0 | 0 | Hello | Nurse | 1 |
| 6 | 3 | 1 | 0 | 0 | Dippity | Doo-Dah | 1 |
|----|-----|-----|----|----|-----------|--------------|----|
Question
How do I write a query to determine whether for any given rid, what changed between the most recent version and the version immediately preceding it (if any) such that it produces something like this:
|-----|-----------------|-----------------|-----------------|
| rid | numbers_changed | strings_changed | boolean_changed |
|-----|-----------------|-----------------|-----------------|
| 1 | TRUE | TRUE | FALSE |
| 2 | FALSE | TRUE | FALSE |
| 3 | n/a | n/a | n/a |
|-----|-----------------|-----------------|-----------------|
I think that I should be able to do this by doing a cross-join between the table and itself but I can't resolve how to perform this join to get the desired output.
I need to generate this "report" for a table with 10's of columns and 1-10 versions of 100's of records (resulting in 1000's of rows). Note the particular design of the database is not my own and altering the structure of the database (at this time) is not an acceptable approach.
The actual format of the output isn't important - and if it simplifies the query getting a "full breakdown" of what changed for each "change set" would also be acceptable, for example
|-----|-----|-----|----|----|----|----|----|
| rid | old | new | n1 | n2 | s1 | s2 | b1 |
|-----|-----|-----|----|----|----|----|----|
| 1 | 1 | 2 | Y | N | N | N | N |
| 1 | 2 | 3 | Y | Y | Y | Y | N |
| 2 | 4 | 5 | N | N | N | Y | N |
|-----|-----|-----|----|----|----|----|----|
Note that it is also ok, in this case to omit rid records which only have a single version, as for the purposes of this report I only care about records that have changed and getting a separate list of records that haven't changed is an easy query
You can join every row with the following one with
select *
from history h1
join history h2
on h2.rid = h1.rid
and h2.id = (
select min(h.id)
from history h
where h.rid = h1.rid
and h.id > h1.id
);
Then you just need to compare every column from the two rows like h1.n1 <> h2.n1 as n1.
The full query would be:
select h1.rid, h1.id as old, h2.id as new
, h1.n1 <> h2.n1 as n1
, h1.n2 <> h2.n2 as n2
, h1.s1 <> h2.s1 as s1
, h1.s2 <> h2.s2 as s2
, h1.b1 <> h2.b1 as b1
from history h1
join history h2
on h2.rid = h1.rid
and h2.id = (
select min(h.id)
from history h
where h.rid = h1.rid
and h.id > h1.id
);
Result:
| rid | old | new | n1 | n2 | s1 | s2 | b1 |
|-----|-----|-----|----|----|----|----|----|
| 1 | 1 | 2 | 1 | 0 | 0 | 0 | 0 |
| 1 | 2 | 3 | 1 | 1 | 1 | 1 | 0 |
| 2 | 4 | 5 | 0 | 0 | 0 | 1 | 0 |
Demo: http://sqlfiddle.com/#!9/2e5d12/5
If the columns can contain NULLs, You might need something like NOT h1.n1 <=> h2.n1 as n1. <=> is a NULL-save equality check.
If the version within a rid group is guaranteed to be consecutive, you can simplify the JOIN to
from history h1
join history h2
on h2.rid = h1.rid
and h2.ver = h1.ver + 1
Demo: http://sqlfiddle.com/#!9/2e5d12/7
I'm having a problem.
I have this table called usersbycourse which shows this information:
+------------+-----------------+--------+-----------+-------+-----------------+-----------------+
| instanceid | shortname | userid | firstname | logid | lastaccessdelta | modulesfinished |
+------------+-----------------+--------+-----------+-------+-----------------+-----------------+
| 2 | PJU | 74 | Robin | 766 | 1662246 | 0 |
| 3 | Fundgest-GRHN1A | 75 | Batman | 867 | 1576725 | 0 |
| 3 | Fundgest-GRHN1A | 77 | Abigobeu | 1004 | 610480 | 0 |
+------------+-----------------+--------+-----------+-------+-----------------+-----------------+
and this SQL:
SELECT
mdl_course.id,
mdl_course.shortname,
COUNT(CASE WHEN usersbycourse.modulesfinished = 1 THEN NULL ELSE 1 END) AS studentcount
FROM mdl_course LEFT JOIN usersbycourse ON mdl_course.id = usersbycourse.instanceid
GROUP BY mdl_course.id;
The results from the SQL are:
+----+-----------------+--------------+
| id | shortname | studentcount |
+----+-----------------+--------------+
| 1 | Unity I | 1 |
| 2 | PJU | 1 |
| 3 | Fundgest-GRHN1A | 2 |
| 4 | asdzxc2 | 1 |
+----+-----------------+--------------+
But why? In inside SQL has no Unity I, and no asdzxc2. How do I produce a result like this:
+----+-----------------+--------------+
| id | shortname | studentcount |
+----+-----------------+--------------+
| 1 | Unity I | 0 |
| 2 | PJU | 1 |
| 3 | Fundgest-GRHN1A | 2 |
| 4 | asdzxc2 | 0 |
+----+-----------------+--------------+
?
EDIT:
I want to count only rows having modulesfinished = 0
What you're looking for is SUM rather than COUNT, that is,
SELECT
mdl_course.id,
mdl_course.shortname,
SUM(CASE WHEN usersbycourse.modulesfinished = 0 THEN 1 ELSE 0 END) AS studentcount
FROM mdl_course LEFT JOIN usersbycourse ON mdl_course.id = usersbycourse.instanceid
GROUP BY mdl_course.id;
The problem is because you are using LEFT JOIN some of the values for usersbycourse.modulesfinished are NULL
Something you need to learn is
NULL == something
Is always unknown, not true, not false, just unknown.
So when you try to compare with = 1 your nulls get the ELSE but not because they aren't 1, is because is all the rest.
So if instead you change the condition to
COUNT(CASE WHEN usersbycourse.modulesfinished = 0 THEN 1 ELSE NULL)
Only the TRUE match will get 1, the FALSE and the UNKNOW part ill get NULL and COUNT doesnt count nulls. And that is what you want.
I do not really know if this is possible to do this but I will expose my problem.
I have two tables cases and progress
cases
+----------+--------------+---------------------+---------+------+
| id_cases | name | date_surgery | archive | done |
+----------+--------------+---------------------+---------+------+
| 1 | Cranioplasty | 2016-02-01 00:00:00 | 1 | 0 |
| 2 | Cranioplasty | 2016-02-02 00:00:00 | 0 | 0 |
| 3 | Other | 2016-02-03 00:00:00 | 0 | 0 |
| 4 | Osteotomy | 2016-02-04 00:00:00 | 0 | 0 |
| 5 | Bone Tumor | 2016-02-05 00:00:00 | 1 | 1 |
+----------+--------------+---------------------+---------+------+
progress (which contains thousands of records)
+-------------+---------+---------+---------+
| id_progress | task_id | case_id | current |
+-------------+---------+---------+---------+
| 1 | 103006 | 1 | 0 |
| 2 | 103002 | 1 | 1 |
| 3 | 103003 | 1 | 1 |
| 4 | 201006 | 5 | 0 |
| 5 | 201007 | 5 | 1 |
| .... | ... | ... | ...|
+-------------+---------+---------+---------+
The link between the tables is cases.id_cases = progress.case_id
I want to select all cases with archive and done = 0. I also want to get some progress that are linked to this case
I tought about a condition to select a specific range of task_id related to the result of cases.name.
So basically I want this
SELECT id_cases, name, date_surgery, task_id, current
FROM cases
LEFT JOIN progress on progress.case_id = cases.id_cases
WHERE archive = 0 AND done = 0
But if name is Cranioplasty I just want progress.task_id that are equal to 103006, 103002 and 105002. For Bone Tumor I want 201006, 205003 and 207001. And this for each different name.
There is no logic between the id_cases and the task_id. I must hardcode this.
I tried differents things but none suceeded
SELECT id_Cases, name, date_surgery, task_id, current
from cases
left join progress on progress.case_id = cases.id_cases
where archive = 0 and done = 0
and case when name='Cranioplasty' then task_id=103006 and task_id=103002 else
case when name='Bone Tumor' then task_id=201006 else
case when name='Osteotomy' then task_id=301002 else
case when name='MBIO' then task_id=401006 end end end end
order by name, date_surgery
In fine I try to get this result (task_id is not important, I just want to result of current)
+------+--------------+-----------+--------+-------+--------+-------+--------+-------+
| case | name | date_surg | task_1 | 1_res | task_2 | 2_res | task_3 | 3_res |
+------+--------------+-----------+--------+-------+--------+-------+--------+-------+
| 1 | Cranioplasty | date | 103006 | 0 | 103002 | 0 | 105002 | 1 |
| 1 | Cranioplasty | date | 103006 | 1 | 103002 | 1 | 105002 | 0 |
| 1 | Cranioplasty | date | 103006 | 1 | 103002 | 0 | 105002 | 1 |
| 2 | Cranioplasty | date | 103006 | 0 | 103002 | 1 | 105002 | 0 |
| 2 | Cranioplasty | date | 103006 | 1 | 103002 | 0 | 105002 | 1 |
| 2 | Cranioplasty | date | 103006 | 0 | 103002 | 1 | 105002 | 1 |
| 3 | Bone Tumor | date | 201006 | 1 | 205003 | 0 | 205005 | 0 |
| 3 | Bone Tumor | date | 201006 | 0 | 205003 | 1 | 205005 | 1 |
| ... | | | | | | | | |
+------+--------------+-----------+--------+-------+--------+-------+--------+-------+
PS : I just put my table as an example to help understanding the problem. It does not includes all the records
I know that I can use temporary or virtual table but I wanted to know how to resolve this with only a query
Well, anyway its bad practice to hardcode this relations between name and task id. You need to store them in database or smthng. So you can join that table and do it in 1 query.
If you cant or dont want to its better to save them atleast to an array so you can dynamically generate query part with this conditions if its possible.
select
a.id_cases,
a.name,
b.task_id,
b.current
from
cases a
left join
progress b ON b.case_id = a.id_cases
where
a.archive = 0
and a.done = 0
and (
(b.task_id in (103006,103002,105002) and a.name = 'Cranioplasty')
OR (b.task_id in (201006,205003,207001) and a.name = 'Bone Tumor')
)
If you can use any language to generate this part
and (
(b.task_id in (103006,103002,105002) and a.name = 'Cranioplasty')
OR (b.task_id in (201006,205003,207001) and a.name = 'Bone Tumor')
)
Do it. For example in php
foreach($arRealtions as $name => $taskIDs)
{
$query .= '(b.task_id in ('.implode(',',$taskIDs).') and a.name = "'.$name.'")';
}
I'm building a website for our ball team for the fun of it and keeping track of stats using PHP and SQL for the database. I've learned both by reading the manuals and through forums. I'm working on building a query that will display the current longest hitting streak. I stumbled across a page about detecting runs and streaks and am trying to work with that. I'm really new to all this stuff, so maybe I've structured my tables incorrectly.
Table "games"
+--------+------------+------+
| GameID | Date | Time |
+--------+------------+------+
| 1 | 2015/08/19 | 6:30 |
| 2 | 2015/08/20 | 6:30 |
| 3 | 2015/08/22 | 6:30 |
| 4 | 2015/08/24 | 8:00 |
| 5 | 2015/08/24 | 6:30 |
| 6 | 2015/07/15 | 8:00 |
+--------+------------+------+
Table "player"
+--------+----+---+
| GameID | AB | H |
+--------+----+---+
| 1 | 3 | 1 |
| 2 | 4 | 2 |
| 3 | 2 | 0 |
| 4 | 3 | 0 |
| 5 | 2 | 1 |
| 6 | 3 | 0 |
+--------+----+---+
Code
SELECT games.GameID, GR.H,
(SELECT COUNT(*)
FROM player G
WHERE (CASE WHEN G.H > 0 THEN 1 ELSE 0 END) <> (CASE WHEN GR.H > 0 THEN 1 ELSE 0 END)
AND G.GameID <= GR.GameID) as RunGroup
FROM player GR
INNER JOIN games
ON GR.gameID = games.GameID
ORDER BY Date ASC, Time ASC
Basically in order to correctly get the hit streak right, I need to reorder the GameIDs on the "player" table based on the Date (ASC) and Time (ASC) on the "games" table before executing the RunGroup part of the code. Obviously by adding the ORDER BY, everything gets sorted only after the RunGroup has finished querying and results in incorrect data. I've been stuck here for a few days and now need some help.
The Result I currently get is:
+--------+---+----------+
| GameID | H | RunGroup |
+--------+---+----------+
| 6 | 0 | 3 |
| 1 | 1 | 0 |
| 2 | 2 | 0 |
| 3 | 0 | 2 |
| 5 | 1 | 2 |
| 4 | 0 | 2 |
+--------+---+----------+
This is what I'm trying to achieve:
+--------+---+----------+
| GameID | H | RunGroup |
+--------+---+----------+
| 6 | 0 | 0 |
| 1 | 1 | 1 |
| 2 | 2 | 1 |
| 3 | 0 | 2 |
| 5 | 1 | 2 |
| 4 | 0 | 3 |
+--------+---+----------+
Thanks
Consider the following:
DROP TABLE IF EXISTS games;
CREATE TABLE games
(game_id INT NOT NULL AUTO_INCREMENT PRIMARY KEY
,date_played DATETIME NOT NULL
);
INSERT INTO games VALUES
(1,'2015/08/19 18:30:00'),
(2,'2015/08/20 18:30:00'),
(3,'2015/08/22 18:30:00'),
(4,'2015/08/24 20:00:00'),
(5,'2015/08/24 18:30:00'),
(6,'2015/07/15 20:00:00');
DROP TABLE IF EXISTS stats;
CREATE TABLE stats
(player_id INT NOT NULL
,game_id INT NOT NULL
,at_bat INT NOT NULL
,hits INT NOT NULL
,PRIMARY KEY(player_id,game_id)
);
INSERT INTO stats VALUES
(1,1,3,1),
(1,2,4,2),
(1,3,2,0),
(1,4,3,0),
(1,5,2,1),
(1,6,3,0),
(2,1,2,1),
(2,2,3,2),
(2,3,3,0),
(2,4,3,1),
(2,5,2,1),
(2,6,3,0);
SELECT x.*
, SUM(y.at_bat) runningAB
, SUM(y.hits) runningH
, SUM(y.hits)/SUM(y.at_bat) BA
FROM
(
SELECT s.*, g.date_played FROM stats s JOIN games g ON g.game_id = s.game_id
) x
JOIN
(
SELECT s.*, g.date_played FROM stats s JOIN games g ON g.game_id = s.game_id
) y
ON y.player_id = x.player_id
AND y.date_played <= x.date_played
GROUP
BY x.player_id
, x.date_played;
+-----------+---------+--------+------+---------------------+-----------+----------+--------+
| player_id | game_id | at_bat | hits | date_played | runningAB | runningH | BA |
+-----------+---------+--------+------+---------------------+-----------+----------+--------+
| 1 | 6 | 3 | 0 | 2015-07-15 20:00:00 | 3 | 0 | 0.0000 |
| 1 | 1 | 3 | 1 | 2015-08-19 18:30:00 | 6 | 1 | 0.1667 |
| 1 | 2 | 4 | 2 | 2015-08-20 18:30:00 | 10 | 3 | 0.3000 |
| 1 | 3 | 2 | 0 | 2015-08-22 18:30:00 | 12 | 3 | 0.2500 |
| 1 | 5 | 2 | 1 | 2015-08-24 18:30:00 | 14 | 4 | 0.2857 |
| 1 | 4 | 3 | 0 | 2015-08-24 20:00:00 | 17 | 4 | 0.2353 |
| 2 | 6 | 3 | 0 | 2015-07-15 20:00:00 | 3 | 0 | 0.0000 |
| 2 | 1 | 2 | 1 | 2015-08-19 18:30:00 | 5 | 1 | 0.2000 |
| 2 | 2 | 3 | 2 | 2015-08-20 18:30:00 | 8 | 3 | 0.3750 |
| 2 | 3 | 3 | 0 | 2015-08-22 18:30:00 | 11 | 3 | 0.2727 |
| 2 | 5 | 2 | 1 | 2015-08-24 18:30:00 | 13 | 4 | 0.3077 |
| 2 | 4 | 3 | 1 | 2015-08-24 20:00:00 | 16 | 5 | 0.3125 |
+-----------+---------+--------+------+---------------------+-----------+----------+--------+
I rebuilt my database to have only one table to contain the stats from all players. From there i was able to use this query to find my longest current hitting streak for a certain player.
SELECT *
FROM (SELECT (CASE WHEN h > 0 THEN 1 ELSE 0 END) As H, MIN(date_played) as StartDate,
MAX(date_played) as EndDate, COUNT(*) as Games
FROM (SELECT date_played, (CASE WHEN h > 0 THEN 1 ELSE 0 END) as H, (SELECT COUNT(*)
FROM stats G WHERE ((CASE WHEN G.h > 0 THEN 1 ELSE 0 END) <> (CASE WHEN GR.h > 0 THEN 1 ELSE 0 END))
AND G.date_played <= GR.date_played AND player_id = 13) as RunGroup
FROM stats GR
WHERE player_id = 13) A
GROUP BY H, RunGroup
ORDER BY Min(date_played)) A
WHERE H = 1
ORDER BY Games DESC
LIMIT 1