How can I create a view that merges different columns with a different table? I have three tables for example: users, items and gifts (in this example it's a system that a user can give a gift to another user)
users table has information about users, items table has information about items and gifts table shows which user sent what gift to which user.
What I want is to create a view like following:
user_from | user_to | gift_name | gift_price
sally | john | Teddy Bear | 10
You must join the three tables first. Example
CREATE VIEW GiftsList
AS
SELECT b.name user_from,
c.name user_to,
d.name gift_name,
d.price gift_price
FROM gift a
INNER JOIN users b
ON a.user_from = b.id
INNER JOIN users c
ON a.user_from = c.id
INNER JOIN items d
ON a.item = d.id
You can create a view with two tables like:
CREATE VIEW giftList AS
SELECT users.user_from,users.user_to,gifts.gift_name,gifts.gift_price FROM users,gifts
WHERE users.user_id = gifts.user_id;
The where clause is to make sure the output does not repeat.
I believe were looking for data blending. So basically having google data studio do a JOIN statement on ids from 2 data sets
Related
Does anyone know the solution to this problem ?
There are 3 Tables: orders, order_groups and stores.
I want to list the orders, with the names of the stores where the order was placed, and where the order is going to be delivered.
I keep the from_store_id, and to_store_id in the order_groups table
Listing these orders would be simple, i just left join the order_groups to orders, and select the name, from_shop_id and to_shop_id, but the problem is i want the name of the stores not the id, and the store names are placed in a different table (stores)
Here is what im talking about:
Table orders
id group_id name madeup_id
1 11 johnny cash 1
2 12 billy bob 1
LEFT JOIN order_groups on order_groups.id = orders.group_id
Table order_groups
id from_store_id to_store_id
11 55 56
12 56 55
Table stores
id store_name
55 thisstore
56 thatstore
The result im looking for is:
name from_store to_store
1.johhny cash thisstore, thatstore
2.billy bob thatstore, thisstore
The statement i have yet:
SELECT
orders.name, something as from_store, something as to_store
FROM orders
LEFT JOIN order_groups on order_groups.id = orders.group_id
somehow join stores on the order_groups.from_store_id = stores.id
WHERE orders.madeup_id = 1
Any idea how to select and join the store names to the query ?
One more question. I actually want to list two kind of orders in one query from different tables too, im on the right track with this structure ?
SELECT a,b FROM a LEFT JOIN b ON b.something=a.something WHERE something
UNION ALL
SELECT a,b FROM c LEFT JOIN c ON c.something=a.something WHERE something
You only need to join 2 times the same table!
SELECT
orders.name, fromStore.store_name as from_store, toStore.store_name as to_store
FROM orders
LEFT JOIN order_groups on order_groups.id = orders.group_id
left join stores fromStore on the order_groups.from_store_id = fromStore.id
left join stores toStore on the order_groups.to_store_id = toStore.id
WHERE orders.madeup_id = 1
I have my shop database and I want to join two tables together.
id_order | reference | id_shop_group | id_shop | id_carrier | id_lang | id_customer | id_cart
This the header row of my orders table and below is the header of customers table.
id_customer | id_shop_group | id_shop | id_gender | firstname | lastname
What I want to do is to join them based on id_customer column. More specifically I want to add all columns of customers except the ones that are already there to orders table based onid_customer. After joining the tables should look like this:
id_order|reference|id_shop_group|id_shop|id_carrier|id_lang|id_customer|id_cart|id_gender|firstname|lastname
When searching for a solution I found INNER JOIN keyword, but I'm not sure how to use it the way I want.
We don't "Add columns to a table". We, instead, submit SQL to the database that returns the result set that we want. In your case we want to Join the two tables and we can do that using an INNER JOIN on your id_customer field that is common between the two tables. We can turn that into it's own table if you want to hold, permanently, those results. It would look something like
SELECT
orders.id_order,
orders.reference,
orders.id_shop_group,
orders.id_shop,
orders.id_carrier,
orders.id_lang,
orders.id_customer,
orders.id_cart,
customer.id_gender,
customer.firstname,
customer.lastname
FROM orders INNER JOIN customer on orders.id_customer = customer.id_customer;
You can tweak the list of fields to be returned from the joining of these tables to suit your needs.
The fact that id_shop and id_shop_group are in both tables suggests they are part of a composite key. You may need to join using all three shared columns to guarantee unique rows. Otherwise you may retrieve duplicate order rows where the customer belongs to more than one shop.
e.g.
SELECT
...
FROM orders INNER JOIN customer on orders.id_customer = customer.id_customer
and orders.id_shop_group = customer.id_shop_group
and orders.id_shop = customer.id_shop
I have a main table with two relations.
Data structure and example:
A/Employee
id fields
1 Mike Miller
2 Lisa Miller
B/Skill
aid name
1 SQL
1 PHP
C/Language
aid name
1 German
I need a query which shows results from the main table and searches for a keyword in the relation tables.
Search for Miller -> Mike Miller, Lisa Miller
Search for SQL -> Mike Miller
Search for German -> Mike Miller
There are 10.000 rows in the main table and 100.000 relations.
I tried it with JOIN but the query is really slow.
Also the same row from the main table is displayed a view several times when there are more than one relations for this row:
Search for Miller
Returns: Mike Miller, Mike Miller
(Mike Miller displayed more than one time)
SELECT fields
FROM A
JOIN B ON id = B.aid JOIN C ON id = C.aid
WHERE fields LIKE '%"+$search+"%' OR B.name LIKE '%"+$search+"%' OR C.name LIKE '%"+$search+"%'"
I tried to fix the second problem with DISTINCT but now rows without relations are not displayed.
I want to display every row from the main table exactly one time. Which query do I need?
The problem with your first query, as you mention yourself, is that you get several duplicate rows returned. Not strange, since I guess the relation between table A and table B & C is one-to-many.
In your next attempt you added DISTINCT, and that will indeed get rid off the duplicates, but the regular join (or inner join) will only return matches where data can be joined, i.e. where data exists in both joined tables.
Introducing LEFT JOIN:
SELECT DISTINCT fields
FROM A
LEFT JOIN B ON id = B.aid
LEFT JOIN C ON id = C.aid
WHERE fields LIKE '%"+$search+"%' OR B.name LIKE '%"+$search+"%' OR C.name LIKE '%"+$search+"%'"
This will always search all data from table A, and those from table B & C where joins can be made. The DISTINCT will make sure that only unique rows are returned. You could also use GROUP BY for the same result, but that's usually used for aggregate methods.
Use LEFT JOIN.
Example:
SELECT distinct e.empname FROM Employee e
LEFT JOIN skill s ON s.aid = e.id
LEFT JOIN lang l ON l.aid = e.id
WHERE e.empname LIKE '%Miller%' OR s.name LIKE '%Miller%' OR l.name LIKE '%Miller%'
Proof SQL Fiddle
I am looking to get a full company list with associated contacts. Even if a company does not have any contacts they should still be included in the results. The Company and People table are linked by a relations value table.
I have created a SQL fiddle for the scheme and would appreciate it if someone could write the query for me.
http://sqlfiddle.com/#!2/34a0a
I would see the result look like:
Company Name 1 | Person Number 1 <br>
Company Name 1 | Person Number 2 <br>
Company Name 2 | Person Number 3 <br>
Company Name 2 | Person Number 4 <br>
Company Name 2 | Person Number 5 <br>
Company Name 2 | Person Number 6 <br>
Company Name 3 | NULL <br>
You can achieve this result with two joins - one to your relations table, then another to your persons table. If you use a left join, the link will not be forced, so the company without a person/relation will still be returned but with null as the person result:
SELECT
C.*,
P.*
FROM
companies C
LEFT JOIN
relations R
ON (R.parentmodule = 'companies' AND R.parentrecordid = C.id)
LEFT JOIN
people P
ON (R.childmodule = 'people' AND R.childrecordid = P.id)
Output
The following query gets the desired output. Since an inner join is used between two tables, it should be slightly faster.
SELECT
c.companyname,
p_r.firstname,
p_r.lastname
FROM companies c
LEFT JOIN
(SELECT
r.parentrecordid,
p.firstname,
p.lastname
FROM relations r
INNER JOIN people p ON p.id = r.childrecordid AND r.childmodule = 'people'
) p_r
ON p_r.parentrecordid = c.id;
SQL Fiddle demo
I have a table, with rows of events, and each one has (amongst lots of other fields) addedbyuser, editedbyuser, deletedbyuser
There are INT, and refer back to the users table to a particular user.
I am able to join one of the fields (say addedbyuser) without any problems, how do i join the rest and reference them in php?
events table:
eventid addedbyuser editedbyuser deletedbyuser
1 1 2 3
users table:
id username
1 name1
2 name2
3 name3
So basically, I want to display the names of who added, edited and deleted the article, can I do this in one SQL query?
Something like this:
select
evn.eventid,
us1.username as addedbyuser,
us2.username as editedbyuser,
us3.username as deletedbyuser,
from events evn
join users as us1 on
evn.addedbyuser = us1.id
join users as us2 on
evn.editedbyuser = us2.id
join users as us3 on
evn.deletedbyuser = us3.id