I want to select all the planes that aren't belong to a certain company. I have three tables in this case: Planes, Companies, and CompanyPlanes.
Here is my query:
SELECT *
FROM planes p,
companyplanes cp,
companies c
WHERE c.id = ?
AND cp.idCompany != c.id
AND (cp.idPlane = p.id OR p.id NOT IN (SELECT idPlane FROM companyplanes))
ORDER BY name ASC
But this query returned nothing! what is the wrong here?
example:
| Plane |
---------
id | name
---------
1 | p1
2 | p2
3 | p3
|Company|
---------
id | name
---------
1 | c1
2 | c2
| companyPlanes |
------------------------
id | idCompany | idPlane
------------------------
1 | 1 | 1
2 | 1 | 2
3 | 2 | 2
if I want to get the planes that are not belong to the company c2 the result should be: p1, p3.
Update Answer
We can get the result in following way
Get all planes of the unexpected company
SELECT idplane from CompanyPlanes
WHERE idCompany = ?
Get all planes without those planes of the unexpected company
SELECT * FROM Planes
WHERE id NOT IN
(
SELECT idplane from CompanyPlanes
WHERE idCompany = ?
)
You don't need to join with Company table as you already get idCompany from CompanyPlanes table.
The inner join requires that the query return rows from planes which have a corresponding row in companyplanes but the subselect excludes any rows which have corresponding records in companyplanes.
Assuming that you want the records from planes which don't have a record in companyplanes, then why are you also selecting from companies?
Select p.*
From planes p
Left join
Companyplanes do
On p.id=cp.idplane
Where cp.idplane is null;
If I understand your question the right way, this is what you might be looking for..
select p.*
from planes p
join companyplanes cp on cp.idPlane=p.id
join companies c on c.id=cp.idCompany
where c.id != ?
Related
My case looks simple but i'm messing around with this..
I have 4 tables: User, Macros, Categories, and another one that relate users with categories. One Macro have many Categories.
What i need, is a query that based on the Macro, get the users and the Categories where user is NOT IN.
Example: I have a macro named VEICULES, with categories CAR,TRUCK and Motorcycle. User José is on category CAR and User Julio on category CAR and TRUCK, so my query should return:
José | TRUCK,Motorcycle
Julio | Motorcycle
Tables:
prd_users
id | name | Email
---------------------------
1 | José | jose#email.com
2 | Júlio | julio#email.com
3 | André | andre#email.com
cat_macros
macro_id | macro_name
-----------------------
1 | Veicules |
cat_categories
category_id | category_name | macro_id
---------------------------------------
1 | Cars | 1
2 | Trucks | 1
3 | Motorcycles | 1
prd_tr_rabbit_catg
id | category_id | tasker_user_id
---------------------------------------
1 | 1 | 1
2 | 1 | 2
3 | 2 | 2
I'm stucked on just getting the categories where the user already is ..
SELECT prd_users.id, prd_users.name,
prd_users.email,cat_macros.macro_name as macro,
GROUP_CONCAT(cat_categories.category_name SEPARATOR ', ') as in_categories
FROM prd_users
INNER JOIN prd_tr_rabbit_catg ON prd_tr_rabbit_catg.tasker_user_id = prd_users.id
INNER JOIN cat_categories ON cat_categories.category_id = prd_tr_rabbit_catg.category_id
INNER JOIN cat_macros ON cat_macros.macro_id = cat_categories.macro_id
WHERE cat_macros.macro_id = '45'
GROUP BY prd_users.id;
To solve this problem it's necessary to create a list of all users joined with all categories for the given macro category. This can be done with a CROSS JOIN:
SELECT *
FROM prd_users u
CROSS JOIN (SELECT m.macro_id, m.macro_name, c.category_name, c.category_id
FROM cat_macros m
JOIN cat_categories c ON c.macro_id = m.macro_id) c
This can then be LEFT JOINed to the prd_tr_rabbit_catg table and by selecting those rows where there is no matching entry in the prd_tr_rabbit_catg table, we can find the users who don't have an entry for the given category:
SELECT c.macro_name, u.id AS user_id, u.name, u.Email, GROUP_CONCAT(c.category_name) AS missing_cats
FROM prd_users u
CROSS JOIN (SELECT m.macro_id, m.macro_name, c.category_name, c.category_id
FROM cat_macros m
JOIN cat_categories c ON c.macro_id = m.macro_id) c
LEFT JOIN prd_tr_rabbit_catg x ON x.tasker_user_id = u.id AND x.category_id = c.category_id
WHERE x.id IS NULL
AND c.macro_id = 1
GROUP BY c.macro_name, u.id
For your sample data, this gives:
macro_name user_id name Email missing_cats
Veicules 1 José jose#email.com Motorcycles,Trucks
Veicules 2 Júlio julio#email.com Motorcycles
Veicules 3 André andre#email.com Cars,Motorcycles,Trucks
Update
To exclude users who don't have any of the categories, add a HAVING clause:
HAVING COUNT(*) < (SELECT COUNT(*) FROM cat_categories WHERE macro_id = 1)
Demo on SQLFiddle
I've been trying for two days, without luck.
I have the following simplified tables in my database:
customers:
| id | name |
| 1 | andrea |
| 2 | marco |
| 3 | giovanni |
access:
| id | name_id | date |
| 1 | 1 | 5000 |
| 2 | 1 | 4000 |
| 3 | 2 | 1500 |
| 4 | 2 | 3000 |
| 5 | 2 | 1000 |
| 6 | 3 | 6000 |
| 7 | 3 | 2000 |
I want to return all the names with their last access date.
At first I tried simply with
SELECT * FROM customers LEFT JOIN access ON customers.id =
access.name_id
But I got 7 rows instead of 3 as expected. So I understood I need to use GROUP BY statemet as the following:
SELECT * FROM customers LEFT JOIN access ON customers.id =
access.name_id GROUP BY customers.id
As far I know, GROUP BY combines using a random row. In fact I got unordered access dates with several tests.
Instead I need to group every customer id with its corresponding latest access! How this can be done?
You have to get the latest date from the access table with a group by on the the name_id, then join this result with the customer table. Here is the query:
select c.id, c.name, a.last_access_date from customers c left join
(select id, name_id, max(access_date) last_access_date from access group by name_id) a
on c.id=a.name_id;
Here is a DEMO on sqlfiddle.
I think this is what you'd like to achieve:
SELECT c.id, c.name, max(a.date) last_access
FROM customers c
LEFT JOIN access a ON c.id = a.name_id
GROUP BY c.id, c.name
The LEFT join will return all entries in table customers regardless if the join criteria (c.id = a.name_id) is satisfied. This means that you might get some NULL entries.
Example:
Simply add a new row in the customers table (id: 4, name: manuela). The output will have 4 rows and the newest row will be (id: 4, last_access: null)
I would do this using a correlated subquery in the ON clause:
SELECT a.*, c.*
FROM customers c LEFT JOIN
access a
ON c.id = a.name_id AND
a.DATE = (SELECT MAX(a2.date) FROM access a2 WHERE a2.name_id = a.name_id);
If this statement is true:
I need to group every customer id with its corresponding latest access! How this can be done?
Then you can simply do:
select a.name_id, max(a2.date)
from access a
group by a.name_id;
You do not need the customers table because:
All customers are in access, so the left join is not necessary.
You need no columns from customers.
I need a help about a little confusing sql query. I have 3 tables. Names : article, category and category_article table.
In my article table, there are 4 columns which are :
aid -> article id
py -> Year of article
totalPoint -> point of Article
tc -> number of cited of article
In category table, there are 2 columns which are :
cid -> category id
category -> name of category
Lastly, in my category_article table, there are 2 columns which are :
cid -> category id
aid -> article id related with category
In the below, there are sample table inputs.
Article Table
______________________________
| aid | py | totalPoint | tc |
-------------------------------
| 1 | 2014| 30 | 3 |
-------------------------------
| 2 | 2013| 20 | 2 |
-------------------------------
| 3 | 2014| 50 | 10 |
_______________________________
Category Table
__________________
| cid | category |
-------------------
| 1 | Surgery |
-------------------
| 2 | Enginering|
____________________
Category_Article Table
__________________
| cid | aid |
-------------------
| 1 | 3 |
-------------------
| 2 | 5 |
____________________
My purpose is find this output with only one sql query.
Category name, year, totalArticleNumber, totalPoint(desc), id of article(the most cited article at that year and at that category), citedTime (Top 20)
The example output is :
_______________________________________________________________________________________
Category name | year | totalArticleNumber | totalPoint | id of article(best) | citedTime |
________________________________________________________________________________________
Surgery | 2013 | 182 | 5234 | 312 | 22 |
_________________________________________________________________________________________
Engineering | 2014 | 189 | 5000 | 10 | 32 |
I can do this table with java programing language. Like first do some query and after that do it second query.
But i need to do it in one query.
I try to use JOIN , HAVING , GROUP BY , DISTINCT and anaother some sql stuff but i cannot succeed.
Any help is appreciated.
EDIT
For example if there are two article with same time cited value, they are shown together.
Like in first two column, the article 419 and 385 same time cited value so they both in table.
There are two options for me.
First way -> Show only one article and limit 20. So in this way i can see 20 different category-year combination.
Second way -> Show the same value timecited articles but i have to see 20 different category-year combination.
This is a little tricky, because you're trying to do a lot of different things here. I would simply break them down and put them back together. First, if you want to JOIN all the tables together, you can use the following syntax:
SELECT *
FROM article a
JOIN category_article ca ON ca.aid = a.aid
JOIN category c ON c.cid = ca.cid;
Now, this will only show articles that are assigned to a category. In other words, if an article doesn't exist in the category_article table, or a category doesn't exist in the category_article table, it won't appear here.
If you want to get the total number of articles for a category per year, you can use the COUNT(*) aggregate function, and the SUM() function to get the total points for that category, and then group by category and year to get the amounts for that group:
SELECT c.category, a.py, COUNT(*) AS numArticles, SUM(totalPoint) AS totalPoints
FROM article a
JOIN category_article ca ON ca.aid = a.aid
JOIN category c ON c.cid = ca.cid
GROUP BY c.cid, a.py;
Next, getting the best article will have to be done using a subquery. I recommend focusing just on that subquery for a moment. You can write one query to get the MAX tc for each category and year, and then join that with your table to get all the matching conditions, like this:
SELECT c.category, a.*
FROM category c
JOIN category_article ca ON c.cid = ca.cid
JOIN article a ON a.aid = ca.aid
JOIN(
SELECT c.cid, a.py, MAX(a.tc) AS maxCited
FROM category c
JOIN category_article ca ON ca.cid = c.cid
JOIN article a ON a.aid = ca.aid
GROUP BY c.cid, a.py) temp ON temp.cid = c.cid AND temp.py = a.py AND temp.maxCited = a.tc;
Once you have that, you can JOIN that subquery with the query above to show the best article information alongside the other group information.
SELECT temp1.category, temp1.py, temp1.numArticles, temp1.totalPoints, temp2.aid AS bestArticle, temp2.tc AS citedTime
FROM(
SELECT c.category, a.py, COUNT(*) AS numArticles, SUM(totalPoint) AS totalPoints
FROM article a
JOIN category_article ca ON ca.aid = a.aid
JOIN category c ON c.cid = ca.cid
GROUP BY c.cid, a.py) temp1
JOIN(
SELECT c.category, a.*
FROM category c
JOIN category_article ca ON c.cid = ca.cid
JOIN article a ON a.aid = ca.aid
JOIN(
SELECT c.cid, a.py, MAX(a.tc) AS maxCited
FROM category c
JOIN category_article ca ON ca.cid = c.cid
JOIN article a ON a.aid = ca.aid
GROUP BY c.cid, a.py) temp ON temp.cid = c.cid AND temp.py = a.py AND temp.maxCited = a.tc) temp2
ON temp1.category = temp2.category AND temp1.py = temp2.py;
Here is an SQL Fiddle example. I am going to play around with how to use fewer JOINS, but for right now it should give you what you want and since your tables are indexed it shouldn't run too slowly.
I think I have a somewhat trivial question but I can't figure out how this works. I have the following Companies and Products tables with a simple Many-To-Many relationship.
How would I have to extend this query, so that the results just contains let's say all companies which have products with id 1 AND 2?
I tried adding wheres and havings wherever I could imagine but all i could get was all companies which have products with id x (without the additional and)
Companies Table
id | name
-----------------
1 | Company 1
2 | Company 2
3 | Company 3
Companies_Products Table
id | product_id | company_id
----------------------------
1 | 1 | 1
2 | 2 | 1
3 | 3 | 1
4 | 1 | 2
5 | 1 | 3
6 | 2 | 3
Products Table
id | name
-----------------
1 | Product A
2 | Product B
3 | Product C
Statement
SELECT companies.name,
companies.id AS company_id,
products.id AS product_id
FROM companies
LEFT JOIN company_products
ON companies.id = company_products.company_id
INNER JOIN products
ON company_products.product_id = products.id
If you want ALL companies with associated products 1 and 2, you can write this query:
SELECT c.name,
c.id AS company_id
FROM companies c
WHERE (SELECT COUNT(*)
FROM company_products cp
WHERE cp.company_id = c.id
AND cp.product_id in ('1', '2')
) = 2
Go to Sql Fiddle
If you want to know informations about associated product in the main query so you must use a join in addition of existing query.
Maybe you could using the following subquery in your query:
SELECT company_id, count(*) as no_companies
FROM Companies_Products
WHERE product_id IN (1, 2)
HAVING count(*) = 2
(In this case company an product must be coupled only once.) It returns all the company_ids with product 1 and 2.
There always some discussion about subquery's and performance, but I don't think you will notice.
You could make this function flexible by using a array.
pseudo code:
$parameter = array(1, 2);
...
WHERE product_id IN $parameter
HAVING count(*) = count($parameter)
Please say so if you need more help.
I have two tables: 'company' and 'order'. The first one contains company info and the second one holds all orders made with a company. (order.company = company.ID).
I am making a query on the first table, for example all companies in the city of New York. I would like to make a join with the order table, so that it immediately shows how many orders for a company was made. I could do this with a simple JOIN query, however, it does not include 0. For example, if a company has no orders yet, it will not show up at all, while it should be in the list with 0 orders.
Desired end result:
----------------------------------------
| ID | Name | ... | Orders |
----------------------------------------
| 105 | Company A | ... | 14 |
| 115 | Company B | ... | 5 |
| 120 | Company C | ... | 0 |
| 121 | Company D | ... | 0 |
----------------------------------------
Thanks in advance!
This is a left join with aggregation:
SELECT c.ID, c.Name, count(o.company) as total
FROM companies c left outer join
orders o
on c.id = o.company
WHERE c.city = 'New York'
GROUP BY c.ID;
In MySQL, it is best to avoid subqueries in the from clause -- where possible -- because the derived table is actually created.
The COUNT() expression is counting the number of matches by counting the number of non-null values in the id field used for the join.
Try this
SELECT com.id,com.name,od.orders FROM compnay AS com
LEFT JOIN orders AS od ON od.company = com.id;
SELECT companies.ID,companies.Name ,orders.total FROM
(SELECT ID,Name FROM company where county ='NEW YORK') companies
LEFT JOIN (SELECT company,COUNT(*) as total FROM order GROUP BY company) orders
ON orders.company = companies.ID