I'm creating a checklist-style program, where files are assigned to checklists, and you check items off of checklists for certain files. I'm trying to run a query that returns all files that are READY for a certain checklist item (items are ordered).
So for example, I am trying to see which files are ready for checklist item number 3, so I need to find all files that have been marked as checked for item number 2, BUT NOT for item number 3.
I would also prefer to NOT use sub-queries, even though I know sub-queries would solve this problem (that's why this is taking so long), since this query will be run for every checklist item, and I feel that sub-queries here would affect performance negatively.
Here is my query so far:
SELECT
DISTINCT f.filename, f.id
FROM
files f LEFT JOIN checklist_item_checklist cic1 LEFT JOIN checklist_check cc1 ON
cc1.checklist_item_checklist_id = cic1.checklist_item_checklist_id ON
cc1.file_id != f.id,checklist_item_checklist cic2,
checklist_check cc2
WHERE
cic1.checklist_item_checklist_id = 2 AND
cic2.order_number = cic1.order_number - 1 AND
cic1.checklist_id = cic2.checklist_id AND
cc2.checklist_item_checklist_id = cic2.checklist_item_checklist_id AND
cc2.file_id = f.id
The table structure is:
files
id (PK)
filename
checklist_item_checklist
checklist_item_checklist_id (PK)
order_number
checklist_check
file_id (FK to files.id)
checklist_item_checklist_id (FK to checklist_item_checklist.checklist_item_checklist_id)
Thanks!
You have lots of syntax errors in your query. I believe you need a subquery.
This should work:
SELECT f.id, f.filename
FROM files f
JOIN checklist_check cc ON cc.file_id = f.id
JOIN checklist_item_checklist cic ON cic.checklist_item_checklist_id = cc.checklist_item_checklist_id AND cc.order_number = 2
WHERE f.id not in(
SELECT f.id,
FROM files f
JOIN checklist_check cc ON cc.file_id = f.id
JOIN checklist_item_checklist cic ON cic.checklist_item_checklist_id = cc.checklist_item_checklist_id AND cc.order_number = 3)
Related
I coding web app for my client and have issue with selecting from database raports with newest revisions.
SELECT
raports.*,
r1.*,
users.*,
(SELECT COUNT(*) FROM changes WHERE changes.changes_raports_id = raports.raports_id) as changes,
(SELECT changes.changes_date FROM changes WHERE changes.changes_raports_id = raports.raports_id ORDER BY changes.changes_date DESC LIMIT 1) as last_change,
(SUM(injuries.injuries_min_procent) / COUNT(injuries_to_raports.injuries_to_raports_id)) as min,
(SUM(injuries.injuries_max_procent) / COUNT(injuries_to_raports.injuries_to_raports_id)) as max
FROM raports
LEFT JOIN users
ON users.users_id = raports.raports_users_id
LEFT JOIN changes
ON changes.changes_raports_id = raports.raports_id
LEFT JOIN raports_to_changes r1
ON r1.raports_to_changes_raports_id = raports.raports_id
LEFT JOIN injuries_to_raports
ON injuries_to_raports.injuries_to_raports_raports_id = r1.raports_to_changes_raports_id
LEFT JOIN injuries
ON injuries_to_raports.injuries_to_raports_injuries_id = injuries.injuries_id
WHERE r1.raports_to_changes_changes_id = (SELECT max(raports_to_changes_changes_id) FROM raports_to_changes r2 WHERE r2.raports_to_changes_raports_id = r1.raports_to_changes_raports_id)
GROUP BY raports.raports_id ORDER BY raports.raports_id ASC;
In columns max and min i have not correct average from injuries. When i checked it and count all injuries i had 36 when true number is 2 but i have 18 revisions. So is logic that i have looped COUNT with all revisions but i want only the newest
I try changing WHERE statements and more LEFT JOINs but nothing helped.
Could someone fixed that code?
Thank you in advanced
Based on the clues revealed by your queries, the data model may look like this:
The select list shows that you need:
users information of a reports_id
aggregated injuries_min_procent and injuries_max_procent at raports_id level. (see cte_raport_injuries)
number of changes of a raports_id (see cte_raport_changes)
the last change_date of a raports_id (see cte_raport_changes)
I'm not sure about the need for raports_of_changes based on information revealed in the question, so I'm going to ignore it for now.
with cte_raport_injuries as (
select r.raports_id,
sum(i.injuries_min_procent) / count(*) as injuries_min_procent,
sum(i.injuries_max_procent) / count(*) as injuries_max_procent
from raports r
join injuries_to_raports ir
on r.raports_id = ir.injuries_to_raports_raports_id
join injuries i
on ir.injuries_to_raports_injuries_id = i.injuries_id
group by r.raports_id),
cte_raport_changes as (
select r.raports_id,
count(c.changes_id) as changes,
max(c.changes_date) as last_change
from raports r
join changes c
on r.raports_id = c.changes_raports_id
group by r.raports_id)
select u.users_id,
r.raports_id,
ri.injuries_min_procent,
ri.injuries_max_procent,
rc.changes,
rc.last_change
from raports r
join users u
on r.raports_users_id = u.users_id
join cte_raport_injuries ri
on r.raports_id = ri.raports_id
join cte_raport_changes rc
on r.raports_id = rc.raports_id;
The result looks like this:
users_id|raports_id|injuries_min_procent|injuries_max_procent|changes|last_change|
--------+----------+--------------------+--------------------+-------+-----------+
1| 11| 15.0000| 25.0000| 2| 2022-12-02|
So my question for you is what's in reports_to_changes that you need and what's its relationship between others? For further involvement from the community, you may want to share the following information in text format:
DDLs of each tables (primary key, foreign key, column names & data types)
Some representable sample data and basic business rules
Expected output
I'm trying to achieve a query which seems simple but I can't make it work correctly. Here's my database tables structures:
members
-> id
-> last_name
-> first_name
activities
-> id
registrations
-> id
-> member_id
tandems
-> id
-> activitie_id
-> registration_member_one
-> registration_member_two
Here's what i want to achieve:
Mutliple members can register to an activity. Then, i group the registrations by tandems. I want a view with all the tandems listed and there's my problem. When I try a query, it gives me multiple rows, duplicated many times.
Below, an example of the table I want to have:
tandems.id | activities.id | registration_member_one.members.last_name | registration_member_two.members.last_name
1 | 3 | John Doe | Jane Doe
Here's the query I'm working on:
SELECT
tandems.*,
memberOne.id, memberOne.last_name, memberOne.first_name,
memberTwo.id, memberTwo.last_name, memberTwo.first_name,
memberOne_registration.member_id as memberOne,
memberTwo_registration.member_id as memberTwo
FROM tandems
JOIN registrations as memberOne_registration
ON memberOne_registration.member_id = tandems.registration_member_one
JOIN members as memberOne ON memberOne.id = memberOne_registration.member_id
JOIN registrations as memberTwo_registration
ON memberTwo_registration.member_id = tandems.registration_member_two
JOIN members as memberTwo ON memberTwo.id = memberTwo_registration.member_id
WHERE activitie_id = 3;
Any help appreciated!
The error is caused by joining wrong column (member_id) of registrations table with tandems table, instead column registrations.id should be used.
SELECT
tandems.*,
memberOne.id, memberOne.last_name, memberOne.first_name,
memberTwo.id, memberTwo.last_name, memberTwo.first_name,
memberOne_registration.id as memberOne,
memberTwo_registration.id as memberTwo
FROM tandems
JOIN registrations as memberOne_registration ON memberOne_registration.id = tandems.registration_member_one
JOIN members as memberOne ON memberOne.id = memberOne_registration.member_id
JOIN registrations as memberTwo_registration ON memberTwo_registration.id = tandems.registration_member_two
JOIN members as memberTwo ON memberTwo.id = memberTwo_registration.member_id
WHERE activitie_id = 3;
Although other query is virtually the same, I hate working with unnecessarily long alias names so worked with "r1" and "r2" for the two instances of the registration table, and "m1" and "m2" for the members joining context.
SELECT
t.id,
t.activitie_id,
m1.last_name LastName1,
m1.first_name FirstName1,
m2.last_name LastName2,
m2.first_name FirstName2
FROM
tandems t
LEFT join registrations r1
ON t.registration_member_one = r1.id
LEFT JOIN members m1
ON r1.member_id = m1.id
LEFT join registrations r2
ON t.registration_member_two = m2.id
LEFT JOIN members m2
ON r2.member_id = m2.id
WHERE
t.activitie_id = 3;
To help you on this and in the future... Although mentally done, I try to mentally draw out how do I get the pieces together from the first table downstream. This can be seen too by the visual indentation almost like a tree view extension from T to R1 to M1, then R2 to M2 is a different branch. I also prefer to list the left table/alias.column = right table/alias.column in the join condition. How does T get to R1, then how does R1 get to M1.
In this, I used LEFT JOIN to each respective registration and member -- just-in-case only one person registered and a second may be pending. Not sure how your registration is actually structured.
I have a catalog that contains directories that can contain directories. The access of a directory can be granted to everyone or restricted to 0 to n user and/or to 0 to n usergroup. Access right is inherited in the hierarchy of group and from a group to its user. Therefore, a user can access a directory if he is allowed OR (he isn't deny AND (his group is allowed OR (his group isn't deny AND (his supergroup is allowed OR etc....
Their can be 1 to n level of groups, even if most of the time, their are typically no more than 3 levels.
I made a sqlfiddle from the schema : http://sqlfiddle.com/#!2/81b28
What I need is to get the list directories inside a given directory that can be accessible by a given user.
What I have so far is the following: this get the content of directory id '3' accessible to the user id '10', who is in usergroup '3' which is in supergroup '1' :
select l.id, l.accessright, ll.parentlibrarydirectoryid, ulc.*, glc1.*, glc2.*
from librarydirectory l
inner join a_librarydirectory_librarydirectory ll on ll.childlibrarydirectoryid = l.id
left join a_user_librarydirectory_canaccess ulc on ulc.librarydirectoryid = l.id
left join ws_user u on u.id = ulc.userid
left join a_group_librarydirectory_canaccess glc1 on glc1.librarydirectoryid = l.id
left join a_group_librarydirectory_canaccess glc2 on glc2.librarydirectoryid = l.id
where
ll.parentlibrarydirectoryid = 3
and (u.id = 10 or u.id is null)
and (glc1.groupid = 3 or glc1.groupid is null)
and (glc2.groupid = 1 or glc2.groupid is null)
and (l.accessright = "n"
or ((ulc.canaccess = "y")
or (ulc.canaccess is null and (glc1.allowedToAccess = 1
or (glc1.allowedToAccess is null and (glc2.allowedToAccess = 1))))));
It is working but I feel that this is not very elegant because I need to query the database to get the hierarchy of group prior to dynamically build the query in order to add as many a_group_librarydirectory_canaccess join and where clause as there are levels in the group hierarchy.
Is there a smarter way?
Thank you for your time
Basically I have three MySQL tables:
Users - contains base information on users
Fields - describes additional fields for said users (e.g. location, dob etc.)
Data - Contains user data described via links to the fields table
With the basic design as follows (the below is a stripped down version)
Users:
ID | username | password | email | registered_date
Fields
ID | name | type
Data:
ID | User_ID | Field_ID | value
what I want to do is search Users by the values for the fields they have, e.g. example fields might be:
Full Name
Town/City
Postcode
etc.
I've got the following, which works when you're only wanting to search by one field:
SELECT `users`.`ID`,
`users`.`username`,
`users`.`email`,
`data`.`value`,
`fields`.`name`
FROM `users`,
`fields`,
`data`
WHERE `data`.`Field_ID` = '2'
AND `data`.`value` LIKE 'london'
AND `users`.`ID` = `data`.`User_ID`
AND `data`.`Field_ID` = `fields`.`ID`
GROUP BY `users`.`ID`
But what about if you want to search for Multiple fields? e.g. say I want to search for Full Name "Joe Bloggs" With Town/City set to "London"? This is the real sticking point for me.
Is something like this possible with MySQL?
I'm going with the assumption that "searching multiple fields" is talking about the Entity-Attribute-Value structure.
In that case, I propose that the first step is to create a derived query - basically, we want to limit the "EAV data joined" to only include the records that have the values we are interested in finding. (I've altered some column names, but the same premise holds.)
SELECT d.userId
FROM data d
JOIN fields f
ON f.fieldId = d.fieldId
-- now that we establish data/field relation, filter rows
WHERE f.type = "location" AND d.value = "london"
OR f.type = "job" AND d.value = "programmer"
This resulting rows are derived from the filtered EAV triplets that match our conditions. Only the userId is selected in this case (as it will be used to join against the user relation), but it is also possible to push fieldId/value/etc through.
Then we can use all of this as a derived query:
SELECT *
FROM users u
JOIN (
-- look, just goes in here :)
SELECT DISTINCT d.userId
FROM data d
JOIN fields f
ON f.fieldId = d.fieldId
WHERE f.type = "location" AND d.value = "london"
OR f.type = "job" AND d.value = "programmer"
) AS e
ON e.userId = u.userId
Notes:
The query planner will figure all the RA stuff out peachy keen; don't worry about this "nesting" as there is no dependent subquery.
I avoid the use of implicit cross-joins as I feel they muddle most queries, this case being a particularly good example.
I've "cheated" and added a DISTINCT to the derived query. This will ensure that at most one record will be joined/returned per user and avoids the use of GROUP BY.
While the above gets "OR" semantics well (it's both easier and I may have misread the question), modifications are required to get "AND" semantics. Here are some ways that the derived query can be written to get such. (And at this point I must apologize to Tony - I forget that I've already done all the plumbing to generate such queries trivially in my environment.)
Count the number of matches to ensure that all rows match. This will only work if each entity is unique per user. It also eliminates the need for DISTINCT to maintain correct multiplicity.
SELECT d.userId
FROM data d
JOIN fields f
ON f.fieldId = d.fieldId
-- now that we establish data/field relation, filter rows
WHERE f.type = "location" AND d.value = "london"
OR f.type = "job" AND d.value = "programmer"
GROUP BY d.userId
HAVING COUNT(*) = 2
Find the intersecting matches:
SELECT d.userId
FROM data d
JOIN fields f ON f.fieldId = d.fieldId
WHERE f.type = "location" AND d.value = "london"
INTERSECT
SELECT d.userId
FROM data d
JOIN fields f ON f.fieldId = d.fieldId
WHERE f.type = "job" AND d.value = "programmer"
Using JOINS (see Tony's answer).
SELECT d1.userId
FROM data d1
JOIN data d2 ON d2.userId = d1.userId
JOIN fields f1 ON f1.fieldId = d1.fieldId
JOIN fields f2 ON f2.fieldId = d2.fieldId
-- requires AND here across row
WHERE f1.type = "location" AND d1.value = "london"
AND f2.type = "job" AND d2.value = "programmer"
An inner JOIN itself provides conjunction semantics when applied outside of the condition. In this case I show "re-normalize" the data. This can also be written such that [sub-]selects appear in the select clause.
SELECT userId
FROM (
-- renormalize, many SO questions on this
SELECT q1.userId, q1.value as location, q2.value as job
FROM (SELECT d.userId, d.value
FROM data d
JOIN fields f ON f.fieldId = d.fieldId
WHERE f.type = "location") AS q1
JOIN (SELECT d.userId, d.value
FROM data d
JOIN fields f ON f.fieldId = d.fieldId
WHERE f.type = "job") AS q2
ON q1.userId = q2.userId
) AS q
WHERE location = "london"
AND job = "programmer"
The above duplicity is relatively easy to generate via code and some databases (such as SQL Server) support CTEs which make writing such much simpler. YMMV.
If I understood you right, this is what you want:
FROM `users`,
`fields`,
`data` `location`
`data` `name`
WHERE `location`.`Field_ID` = '2'
AND `location`.`value` LIKE 'london'
AND `location`.`Field_ID` = `fields`.`ID`
AND `name`.`Field_ID` = 'whathere? something for its name'
AND `name`.`value` LIKE 'london'
AND `name`.`Field_ID` = `fields`.`ID`
AND `users`.`ID` = `data`.`User_ID`
I'd prefer joins though
Well here you hit one of the downsides of the EAV you are using
SELECT u.ID, u.username,u.email, d1.value, f1.Name, d2.Value, f2.name
FROM `users` u,
inner join data d1 On d1.User_id = u.id
inner join data d2 On d2.User_id = u.id
inner join fields f1 on f1.id = d1.field_id
inner join fields f2 on f2.id = d2.field_id
WHERE d1.Field_id = '2' and d1.Value = 'london'
and d2.field_id = '??' and d2.value = 'Joe Bloggs'
GROUP BY `users`.`ID`
Messy isn't it? Bet you can't wait to go for, four or five values. Or think about (Forename = Joe Or surname = Bloggs) and City = London...
I have 3 tables
person (id, name)
area (id, number)
history (id, person_id, area_id, type, datetime)
In this tables I store the info which person had which area at a specific time. It is like a salesman travels in an area for a while and then he gets another area. He can also have multiple areas at a time.
history type = 'I' for CheckIn or 'O' for Checkout.
Example:
id person_id area_id type datetime
1 2 5 'O' '2011-12-01'
2 2 5 'I' '2011-12-31'
A person started traveling in area 5 at 2011-12-01 and gave it back on 2011-12-31.
Now I want to have a list of all the areas all persons have right now.
person1.name, area1.number, area2.number, area6.name
person2.name, area5.number, area9.number
....
The output could be like this too (it doesn't matter):
person1.name, area1.number
person1.name, area2.number
person1.name, area6.number
person2.name, area5.number
....
How can I do that?
This question is, indeed, quite tricky. You need a list of the entries in history where, for a given user and area, there is an 'O' record with no subsequent 'I' record. Working with just the history table, that translates to:
SELECT ho.person_id, ho.area_id, ho.type, MAX(ho.datetime)
FROM History AS ho
WHERE ho.type = 'O'
AND NOT EXISTS(SELECT *
FROM History AS hi
WHERE hi.person_id = ho.person_id
AND hi.area_id = ho.area_id
AND hi.type = 'I'
AND hi.datetime > ho.datetime
)
GROUP BY ho.person_id, ho.area_id, ho.type;
Then, since you're really only after the person's name and the area's number (though why the area number can't be the same as its ID I am not sure), you need to adapt slightly, joining with the extra two tables:
SELECT p.name, a.number
FROM History AS ho
JOIN Person AS p ON ho.person_id = p.id
JOIN Area AS a ON ho.area_id = a.id
WHERE ho.type = 'O'
AND NOT EXISTS(SELECT *
FROM History AS hi
WHERE hi.person_id = ho.person_id
AND hi.area_id = ho.area_id
AND hi.type = 'I'
AND hi.datetime > ho.datetime
);
The NOT EXISTS clause is a correlated sub-query; that tends to be inefficient. You might be able to recast it as a LEFT OUTER JOIN with appropriate join and filter conditions:
SELECT p.name, a.number
FROM History AS ho
JOIN Person AS p ON ho.person_id = p.id
JOIN Area AS a ON ho.area_id = a.id
LEFT OUTER JOIN History AS hi
ON hi.person_id = ho.person_id
AND hi.area_id = ho.area_id
AND hi.type = 'I'
AND hi.datetime > ho.datetime
WHERE ho.type = 'O'
AND hi.person_id IS NULL;
All SQL unverified.
You're looking for results where each row may have a different number of columns? I think you may want to look into GROUP_CONCAT()
SELECT p.`id`, GROUP_CONCAT(a.`number`, ',') AS `areas` FROM `person` a LEFT JOIN `history` h ON h.`person_id` = p.`id` LEFT JOIN `area` a ON a.`id` = h.`area_id`
I haven't tested this query, but I have used group concat in similar ways before. Naturally, you will want to tailor this to fit your needs. Of course, group concat will return a string so it will require post processing to use the data.
EDIT I thikn your question has been edited since I began responding. My query does not really fit your request anymore...
Try this:
select *
from person p
inner join history h on h.person_id = p.id
left outer join history h2 on h2.person_id = p.id and h2.area_id = h.area_id and h2.type = 'O'
inner join areas on a.id = h.area_id
where h2.person_id is null and h.type = 'I'