I'm getting crazy to create an insert to a table from a select of same model.
I think that I should create a temp table to elaborate all model, but how?
Here the table I have:
Table product
+------------+----------+
| id_product | id_model |
+------------+----------+
| 1 | D |
| 2 | D |
| 3 | A |
| 4 | C |
| 5 | D |
+------------+----------+
Here the table I would like to create, but my best problem is that the record in related should be duplicate like
id1->id2 and id2->id1
Table related
+------------+-----------------+
| id_product | related_product |
+------------+-----------------+
| 1 | 2 |
| 1 | 5 |
| 2 | 1 |
| 2 | 5 |
| 5 | 1 |
| 5 | 2 |
+------------+-----------------+
Hmmm. I think you just want a self-join
select p1.id_product, p2.id_product as related_product
from product p1 join
product p2
on p1.id_model = p2.id_model and
p1.id_product <> p2.id_product;
Related
I have two MySQL tables (table_a and table_b) and a join table (table_c).
Table Structures:
table_a:
__________________
| table_a: |
|----------------|
| id |
| result_column |
------------------
table_b:
__________________
| table_b: |
|----------------|
| id |
| name |
------------------
table_c:
__________________
| table_c: |
|----------------|
| id |
| table_a_id |
| table_b_id |
------------------
My Goal:
I want to find a query that will:
Iterate over every table_a record and get the table_a.id value
Find any records in table_c which have a matching table_c.table_a_id value
For each matching record in table_c get the table_c.table_b_id value
Find the record in table_b which has a matching table_b.id value
For that matching record in table_b get the table_b.name value
In table_a, concatenate each matched name value into the corresponding table_a.result_column
Example:
Before the Query:
_______________________ _________________________________ ________________
| table_a: | | table_c: | | table_b: |
|---------------------| |-------------------------------| |--------------|
| id | result_column | | id | table_a_id | table_b_id | | id | name |
|-----|---------------| |-----|------------|------------| |-----|--------|
| 1 | | | 1 | 1 | 3 | | 1 | Kevin |
| 2 | | | 2 | 1 | 4 | | 2 | Jesse |
| 3 | | | 3 | 2 | 2 | | 3 | Karen |
----------------------- | 4 | 3 | 1 | | 4 | Tim |
| 5 | 3 | 5 | | 5 | Lauren |
--------------------------------- ----------------
After the Query:
_______________________ _________________________________ ________________
| table_a: | | table_c: | | table_b: |
|---------------------| |-------------------------------| |--------------|
| id | result_column | | id | table_a_id | table_b_id | | id | name |
|-----|---------------| |-----|------------|------------| |-----|--------|
| 1 | Karen, Tim | | 1 | 1 | 3 | | 1 | Kevin |
| 2 | Jesse | | 2 | 1 | 4 | | 2 | Jesse |
| 3 | Kevin, Lauren | | 3 | 2 | 2 | | 3 | Karen |
----------------------- | 4 | 3 | 1 | | 4 | Tim |
| 5 | 3 | 5 | | 5 | Lauren |
--------------------------------- ----------------
For absolute clarity, I understand that this is incredibly bad practice within a relational data-table. This is as far from normalization as one can get. I would never design a database like this. I was tasked with creating a custom column with a list of values purely for a business case.
The query you seem to want is:
select c.table_a_id, group_concat(b.name separator ', ')
from c join
b
on c.table_b_id = b.id
group by c.table_a_id;
If you actually want to update a, you can put this into an update statement:
update a join
(select c.table_a_id, group_concat(b.name separator ', ') as names
from c join
b
on c.table_b_id = b.id
group by c.table_a_id
) cb
on cb.table_a_id = a.id
set result_column = cb.names
Previous answer is close; but you also required that you only want the records matched in table C that are in A.
The first query does not meet this requirement; but the update statement does, as it will only update records in table A, if the id matches the table_a_id value pulled from table C.
Given what you said you wished for the end result, the update statement above would work.
If you wish to be explicit in your logic, just add a join from table A to table C.
select a.id, group_concat(b.name separator ', ')
from a
join c ON (a.id = c.table_a_id)
join b ON (c.table_b_id = b.id)
group by a.id;
I have this tables People, Ticket, and Report.
+----------+-------+-----+
| idPeople | Name | Age |
+----------+-------+-----+
| 1 | Name1 | 21 |
| 2 | Name2 | 37 |
| 3 | Name3 | 28 |
+----------+-------+-----+
I would like to replace the ForeingKey idPeople with columns Name and Age from People table.
+----------+------------+------------+----------+
| idTicket | ticketCol2 | ticketCol3 | idPeople |
+----------+------------+------------+----------+
| 5 | True | 01/06/99 | 1 |
| 6 | False | 01/06/99 | 2 |
| 7 | True | 01/06/99 | 4 |
+----------+------------+------------+----------+
In the Report table replace the Foreing Key idTicket with ticketCol2, Name, Age from the previous table Ticket with replaced columns (idPeople by Name, Age).
+----------+----------+------------+------------+
| idReport | idTicket | ReportCol3 | ReportCol4 |
+----------+----------+------------+------------+
| 1 | 5 | 01/06/99 | blabla |
| 2 | 7 | 01/06/99 | asdfdd |
| 2 | 6 | 01/06/99 | fooboo |
+----------+----------+------------+------------+
And I the result should be like this table and must be done in one query.
+----------+------------+------------+------------+------------+------+-----+
| idReport | ticketCol2 | ticketCol3 | ReportCol3 | ReportCol4 | Name | Age |
+----------+------------+------------+------------+------------+------+-----+
| 1 | 01/06/99 | abcd | blabla | 123456 | Name | 20 |
| 2 | 01/06/99 | bcda | asdfdd | 321456 | Name | 23 |
| 3 | 01/06/99 | asdf | fooboo | 123456 | Name | 28 |
+----------+------------+------------+------------+------------+------+-----+
I Have tried replacing the foreingkeys with LEFT JOIN and bringing some columns Name and Age to the Ticket table but now the last part where I should replace idTicket with Columns from Ticket is not working.
I have read about the nested JOINs but I cannot understand it very well, I would really appreciate some idea of how I can do it or what should I investigate. Are nested Joins the right way?
The query that I've tried to accomplish the Table Ticket.
SELECT Ticket.ticketCol2, Ticket.ticketCol3, p.Name 'Name', p.Age 'Age'
from Ticket
left join people p on (Ticket.idPeople=p.idPeople);
Try something like this:
SELECT Report.idReport,
Ticket.ticketCol2,
Ticket.ticketCol3,
Report.ReportCol3,
Report.ReportCol4,
People.Name,
People.Age
FROM People
LEFT JOIN Ticket ON Ticket.idPeople = People.idPeople
LEFT JOIN Report ON Report.idTicket = Ticket.idTicket
Like #RiggsFolly said, the Ticket.idPeople won´t match to the People.idPeople, so this will not match any rows.
I am stuck in this situation where I need to use Row Number and Column Number values from table's columns to derive the output mentioned below. I have tried everything - if/else, case when/then but not helping.
Any help/suggestions are really appreciated!
Here is a mocked up sample data present in db table -
+--------+--------+--------+----------+-------------+
| Record | ColNbr | RowNbr | ColTitle | CellContent |
+--------+--------+--------+----------+-------------+
| 1 | 1 | 1 | Unit | sqf |
| 1 | 1 | 2 | Unit | cm |
| 1 | 2 | 1 | Desc | roof |
| 1 | 2 | 2 | Desc | rod |
| 1 | 3 | 1 | Material | concrete |
| 1 | 3 | 2 | Material | steel |
| 1 | 4 | 1 | Quantity | 100 |
| 1 | 4 | 2 | Quantity | 12 |
| 1 | 1 | 1 | Unit | liter |
| 1 | 1 | 2 | Unit | ml |
| 1 | 2 | 1 | Desc | bowl |
| 1 | 2 | 2 | Desc | plate |
| 1 | 3 | 1 | Material | plastic |
| 1 | 3 | 2 | Material | glass |
| 1 | 4 | 1 | Quantity | 2 |
| 1 | 4 | 2 | Quantity | 250 |
+--------+--------+--------+----------+-------------+
Expected Output -
+--------+--------+--------+----------+-------------+
| Record | Unit | Desc | Material | Quantity |
+--------+--------+--------+----------+-------------+
| 1 | sqf | roof | concrete | 100 |
| 1 | cm | rod | steel | 12 |
| 2 | liter | bowl | plastic | 2 |
| 2 | ml | plate | glass | 250 |
+--------+--------+--------+----------+-------------+
If your actual data is like that, I suggest that you consider to separate the data to; for example, 4 different tables (unit,description,material & a table to store all that ids+quantity). The former 3 tables will store the prerequisite info that get minor updates throughout time and the last table will store all the quantity records. Let's say your tables will look something like this:
CREATE TABLE `Unit` (
unit_id INT,
unit_name VARCHAR(50));
+---------+-----------+
| unit_id | unit_name |
+---------+-----------+
| 1 | sqf |
| 2 | cm |
| 3 | liter |
| 4 | ml |
+---------+-----------+
CREATE TABLE `Description` (
desc_id INT,
desc_name VARCHAR(50));
+---------+-----------+
| desc_id | desc_name |
+---------+-----------+
| 1 | roof |
| 2 | rod |
| 3 | bowl |
| 4 | plate |
+---------+-----------+
CREATE TABLE `Material` (
mat_id INT,
mat_name VARCHAR(50));
+--------+----------+
| mat_id | mat_name |
+--------+----------+
| 1 | concrete |
| 2 | steel |
| 3 | plastic |
| 4 | glass |
+--------+----------+
CREATE TABLE `Records` (
unit_id INT,
desc_id INT,
mat_id INT,
quantity DECIMAL(14,4));
+---------+---------+--------+----------+
| unit_id | desc_id | mat_id | Quantity |
+---------+---------+--------+----------+
| 1 | 1 | 1 | 100 |
| 2 | 2 | 2 | 12 |
| 3 | 3 | 3 | 2 |
| 4 | 4 | 4 | 250 |
+---------+---------+--------+----------+
Then you insert the data accordingly.
Anyhow, for your existing data example, it could be done but there are some concern over whether the unit+desc+material+quantity matching are correct. The only way I can maybe at least think that it's correctly matched is by giving all of the query a similar ORDER BY clause. Hence, the following:
SELECT A.record,A.unit,B.Desc,C.Material,D.Quantity FROM
(SELECT #rn:=#rn+1 AS record,CASE WHEN coltitle='unit' THEN cellcontent END AS Unit
FROM yourtable, (SELECT #rn :=0 ) v
HAVING unit IS NOT NULL
ORDER BY colnbr) A LEFT JOIN
(SELECT #rn1:=#rn1+1 AS record,CASE WHEN coltitle='Desc' THEN cellcontent END AS `Desc`
FROM yourtable, (SELECT #rn1 :=0 ) v
HAVING `Desc` IS NOT NULL
ORDER BY colnbr) B ON a.record=b.record LEFT JOIN
(SELECT #rn2:=#rn2+1 AS record,CASE WHEN coltitle='material' THEN cellcontent END AS Material
FROM yourtable, (SELECT #rn2:=0 ) v
HAVING Material IS NOT NULL
ORDER BY colnbr) C ON a.record=c.record LEFT JOIN
(SELECT #rn3:=#rn3+1 AS record,CASE WHEN coltitle='Quantity' THEN cellcontent END AS Quantity
FROM yourtable, (SELECT #rn3:=0 ) v
HAVING Quantity IS NOT NULL
ORDER BY colnbr) D ON a.record=d.record;
The idea here is to make a sub-query based on COLTITLE then assign a numbering/ranking (#rn,#rn1,#rn2,#rn3) variable to each of the sub-query and join them up using LEFT JOIN. Now, this experiment works to exactly return the output that you need but its not a definite answer because there are some part that is questionable especially on matching the combination correctly. Hopefully, this will give you some idea.
Complete newbie to mySQL. So any help will be appreciated.
I have 3 tables -- carts, users, actions.
carts:
+------------+-------------+-------+
| cartId | session_id | userId|
+------------+-------------+-------+
users:
+----------+-------------+
| usedId | email |
+----------+-------------+
actions:
+-------------+------------------+---- ---------+
| session_id | impressionAction | impressionId |
+-------------+------------------+-----+--------+
In carts, there is one session_id per line.
In users, there is one userId per line.
In actions, there are multiple lines per session_id counting for all the actions for that session.
I would like to JOINthe three tables getting the output to be something like
+------+-------------+--------+------------------+--------------+-------+
userId | session_id | cartId | impressionAction | impressionId | email |
+------+-------------+--------+------------------+--------------+-------+
Where there will be multiple lines per userId and session_id; essentially a flattened file. I think if we JOIN carts and users on userId resulting in say A and then JOIN A and actions' onsession_id`, we are home.
A sample expected output is:
+------------+-------------+--------+------------------+--------------+---------+
userId | session_id | cartId | impressionAction | impressionId | email |
+------------+-------------+--------+------------------+--------------+---------+
| 1234 | abc3f45 | 0001 | LOGIN | 2032 |ab#yc.com|
| 1234 | abc3f45 | 0001 | ADD | 4372 |ab#yc.com|
| 1234 | abc3f45 | 0001 | ADD | 4372 |ab#yc.com|
| 1234 | abc3f45 | 0001 | SENDMAIL | ab#yc.com |ab#yw.com|
| 4567 | def4rg4 | 0002 | LOGIN | 2032 |db#yw.com|
| 4567 | def4rg4 | 0002 | ADD | 4372 |db#yw.com|
| 4567 | def4rg4 | 0002 | REMOVE | 3210 |db#yw.com|
+------------+-------------+--------+------------------+--------------+---------+**
I don't know how to JOIN 3 tables without one common key. I don't even know what type of join it is called.
Essentially, we are trying to join 3 tables with non-overlapping keys, gathering one common key through the first JOIN and then joining the intermediate with the third one. Is this called a CROSS JOIN? If no, is there a name?
Taken from your comment above
A USER may select many products, add them to their CART; a single
USER may have multiple CARTS and at the end of the event, they can
EMAIL the cart to themselves; the ACTIONS of the user are stored in
the actions table
This is how I see the structure (having in mind your data)
+---------------------+ +---------------------+ +---------------------+
| users | | carts | | actions |
+---------------------+ +---------------------+ +---------------------+
| user_id [PK] |--| | cart_id [PK] | | impression_id [PK] |
| email | |--| user_id [FK] | | action_name |
| | | product_id [FK] | |--| session_id [FK]* |
+---------------------+ | session_id [FK]* |--| | |
| | +---------------------+
+---------------------+
As you can see above, I'm joining first with carts and them with actions because only the table carts has both, user and session data.
The [FK]* next to the session_id on carts and actions could seem as a foreign key but in this case it's not - 'cause there's no separate table for sessions where it would be placed as an PK (primary key)
You asked about join - it is the same as inner join. INNER JOIN creates a new result table by combining column values of two tables (A and B) based upon the join-predicate. The query compares each row of A with each row of B to find all pairs of rows which satisfy the join-predicate.
This is a possible content of the tables
+------------------------+
| users |
+------------------------+
| id | email |
+------+-----------------+
| 1 | first#mail.org |
| 2 | second#mail.org |
| 3 | third#mail.org |
+------+-----------------+
+------------------------------------------+
| carts |
+------------------------------------------+
| id | user_id | product_id | session_id |
+------+---------+------------+------------+
| 1 | 1 | 5 | 1aaaa |
| 2 | 2 | 5 | 2ffff |
| 3 | 3 | 8 | 3ddddd |
| 4 | 1 | 5 | 1aaaaa |
| 5 | 3 | 9 | 3bbbbb |
| 6 | 1 | 6 | 1ccccc |
+------+---------+------------+------------+
+-------------------------------+
| actions |
+-------------------------------+
| id | name | session_id |
+------+-----------+------------+
| 1 | ADD | 1aaaa |
| 2 | ADD | 2ffff |
| 3 | SENDMAIL | 3ddddd |
| 4 | ADD | 3ddddd |
| 5 | SENDMAIL | 2ffff |
| 6 | ADD | 1aaaaa |
| 7 | REMOVE | 3ddddd |
| 8 | ADD | 1ccccc |
| 9 | ADD | 3bbbbb |
| 10 | SENDMAIL | 3bbbbb |
+------+-----------+------------+
As you can see, there are six products in the table carts and exactly six add actions in the table actions. Furthermore, as you can see user with an id=1 bought three products but not at the same time, since there are two sessions; user with an id=3 as well, bought these two products in different times etc...
The SQL statement
SELECT u.user_id, c.session_id, c.cart_id, a.impression_id, a.action_name, u.email
FROM users AS u
INNER JOIN carts AS c ON c.user_id = u.user_id
INNER JOIN actions AS a ON a.session_id = c.session_id
ORDER BY u.user_id, c.session_id, c.cart_id
Results:
+---------+------------+---------+---------------+-------------+-----------------+
| user_id | session_id | cart_id | impression_id | action_name | email |
+---------+------------+---------+---------------+-------------+-----------------+
| 1 | 1aaaa | 1 | 1 | ADD | first#mail.org |
| 1 | 1aaaa | 1 | 6 | ADD | first#mail.org |
| 1 | 1aaaa | 4 | 1 | ADD | first#mail.org |
| 1 | 1aaaa | 4 | 6 | ADD | first#mail.org |
| 1 | 1cccc | 6 | 8 | ADD | first#mail.org |
| 2 | 2ffff | 2 | 5 | SENDMAIL | second#mail.org |
| 2 | 2ffff | 2 | 2 | ADD | second#mail.org |
| 3 | 3bbbb | 5 | 9 | ADD | third#mail.org |
| 3 | 3bbbb | 5 | 10 | SENDMAIL | third#mail.org |
| 3 | 3dddd | 3 | 3 | SENDMAIL | third#mail.org |
| 3 | 3dddd | 3 | 4 | ADD | third#mail.org |
| 3 | 3dddd | 3 | 7 | REMOVE | third#mail.org |
+---------+------------+---------+---------------+-------------+-----------------+
Note: There's no guarantee for session uniqueness.
(Updated) Working SQL Fiddle
UPDATE: (Finding and deleting duplicates)
I've updated the SQL Fiddle in order to simulate duplicate records (when user added the same product within the same session). With the following statement you'll be able to retrieve those duplicated rows.
SELECT c.card_id, c.user_id, c.product_id, c.session_id, a.action_name, a.impression_id
FROM cards As c
INNER JOIN actions AS a ON a.session_id = c.session_id
GROUP BY c.user_id, c.product_id, c.session_id, a.action_name
HAVING count(*) > 1
Results:
+---------+------------+------------+------------+-------------+-----------------+
| card_id | user_id | product_id | session_id | action_name | impression_id |
+---------+------------+------------+------------+-------------+-----------------+
| 1 | 1 | 5 | 1aaaa | ADD | 1 |
| 6 | 1 | 6 | 1cccc | ADD | 8 |
+---------+------------+------------+------------+-------------+-----------------+
In the SELECT part of the statement above you may omit everything except card_id and impression_id. Deleting these two duplicates in one statement is a bit tricky since you can't modify the same table selected in a sub-query within the same query. I would avoid the tricky part in this case (which involves another inner sub-query) and would delete duplicates using separate statements as following
-- delete duplicates from cards
--
DELETE FROM WHERE card_id IN (1,6)
-- delete duplicates from actions
--
DELETE FROM WHERE card_id IN (1,8)
Even better, you could check if the user already has been added a selected product and don't add it twice.
Excuse my MySql syntax, as I don't know it :-p But this is the idea
SELECT u.userId, a.session_id, c.cartId, a.impressionAction, a.impressionId, u.email
FROM Carts c
JOIN Users u on u.userId = c.UserId
JOIN Actions a on a.session_id = c.session_id
This will just merge everything together, and you'll have duplicate cart records if you have many to 1 relationships
Ok, I realize this may be incredibly simple, but my brain is frozen right now. Need a bit of assistance with this query. Let's break it down.
I have two tables (per this example) and I want to update a single table "undeliverable" status
Customers Table (tbl_customers):
+------------+-------------+
| customerID | custAcctNum |
+------------+-------------+
| 1 | 100100121 |
| 2 | 100100122 |
| 3 | 100100123 |
| 4 | 100100124 |
| 5 | 100100125 |
+------------+-------------+
Address Table (tbl_address):
+-----------+------------+---------------+
| addressID | customerID | undeliverable |
+-----------+------------+---------------+
| 1 | 1 | 0 |
| 2 | 2 | 0 |
| 3 | 3 | 0 |
| 4 | 4 | 0 |
| 5 | 5 | 0 |
+-----------+------------+---------------+
Dataset with "undeliverable" Customer Account numbers (custAcctNum)
100100121, 100100123, 100100124
And the query will update the Address Table to this
+-----------+------------+---------------+
| addressID | customerID | undeliverable |
+-----------+------------+---------------+
| 1 | 1 | 1 |
| 2 | 2 | 0 |
| 3 | 3 | 1 |
| 4 | 4 | 1 |
| 5 | 5 | 0 |
+-----------+------------+---------------+
This is the query that I have tried to use
UPDATE tbl_address
SET undeliverable = 1 WHERE
( SELECT custAcctNum FROM tbl_customers AS c
INNER JOIN tbl_address AS a ON a.customerID = c.customerID )
IN ( 100100121, 100100123, 100100124);
Any suggestions? Thanks!
Use mysql's multiple-table update syntax:
update tbl_Address t
join custAcctNum c
on c.customerid = t.customerid
set t.undeliverable = 1
where c.custAcctNum in (100100121, 100100123, 100100124)
UPDATE tbl_address
SET (undeliverable = 1)
WHERE customerID IN (
SELECT customerID
FROM tbl_customers
WHERE custAcctNum IN (100100121, 100100123, 100100124)
);