Need a little help solving problem. Apologies if this is vague which is why I need help. Show The title ID, title, publisher id, publisher name, and terms for all books that have never been sold. This means that there are no records in the Sales Table. Use OUTER JOIN or NOT IN against SALES table. In this case, the terms are referring to the items on the titles table involving money. ( Price, advance, royalty ).
I've come up with the following code and there are no records returned. I've looked at the tables and no records should be returned. Not sure my code is correct based on using the OuterJoin or NOT IN. Thanks!
SELECT titles.title_id,
titles.title,
publishers.pub_id,
sales.payterms,
titles.price,
titles.advance,
titles.royalty
FROM publishers
INNER JOIN titles
ON publishers.pub_id = titles.pub_id
INNER JOIN sales
ON titles.title_id = sales.title_id
WHERE (sales.qty = 0)
I believe all you need it to change the INNER JOIN to a LEFT JOIN for your sales table. Then check for NULL on any of the columns from the sales table.
SELECT titles.title_id, titles.title, publishers.pub_id, sales.payterms,
titles.price, titles.advance, titles.royalty
FROM publishers INNER JOIN
titles ON publishers.pub_id = titles.pub_id LEFT JOIN
sales ON titles.title_id = sales.title_id
WHERE sales.qty IS NULL
Well, you are using INNER JOIN so it will only return records that match the join condition which is not what you want. You should use LEFT OUTER JOIN (or LEFT JOIN) and check that the sales side is null (meaning there's no record matching).
SELECT titles.title_id, titles.title, publishers.pub_id, sales.payterms,
titles.price, titles.advance, titles.royalty
FROM publishers INNER JOIN
titles ON publishers.pub_id = titles.pub_id LEFT OUTER JOIN
sales ON titles.title_id = sales.title_id
WHERE sales.title_id IS NULL
IS NULL Means that a data value does not exist in the database. And just change your INNER JOIN TO LEFT JOIN.
use this..
SELECT titles.title_id,
titles.title,
publishers.pub_id,
sales.payterms,
titles.price,
titles.advance,
titles.royalty
FROM publishers
INNER JOIN titles
ON publishers.pub_id = titles.pub_id
LEFT JOIN sales
ON titles.title_id = sales.title_id
WHERE (sales.qty IS NULL)
Related
Given this Diagram:
What is the right way to use join that will includes all necessary fields from different tables (person name, employee number, status of contracts, job name, department name, pcn/item name, country, and religion)? BUT I want also to include all persons that choose not to put either thier country or religion. I have this query:
SELECT persons.fullname, religions.religion_name, countries.country_name
FROM countries INNER JOIN (religions INNER JOIN (persons INNER JOIN
((jobs INNER JOIN (departments INNER JOIN pcns ON departments.ID = pcns.department_id) ON jobs.ID = pcns.job_id)
INNER JOIN (employees INNER JOIN contracts ON employees.ID = contracts.employee_id) ON pcns.ID = contracts.pcn_id)
ON persons.ID = employees.person_id) ON religions.ID = persons.religion) ON countries.ID = persons.country_id;
I used LEFT JOIN but I got an error. Right now, I only query all my tables except for countries and religions then I made a function that whenever a user clicks particular person this function will return its religion and/or country. I am just curious how to achieve it in a SELECT query.
I am trying to create normalization 3 nf (normal form) in this database. However, when I execute the query, the table is empty. As you will see, this is my table and diagram.
Here is the relationship that we want to 3NF
Torder->(Customer-Food-Carrier-Waiter)-(Ternary Relationship)-(Customer_id,Food_id,Carrier_id,Waiter_id)
Here is my query
SELECT
Customers.ID AS CustomerID,
Food.ID AS FoodID,
Carrier.ID AS CarrierID,
Waiter.ID AS WaiterID,
tOrder.ID AS TORDERID
FROM
tOrder
INNER JOIN
Customers ON Customers.ID = tOrder.Customer_id
INNER JOIN
Food ON Food.ID = tOrder.Food_id
INNER JOIN
Carrier ON Carrier.ID = tOrder.Carrier_id
INNER JOIN
Waiter ON Waiter.ID = tOrder.Waiter_id
ORDER BY tOrder.ID;
Clearly, you have an issue where some of the tables are empty or the ids do not match. You can use LEFT JOIN to keep all orders and see what is happening:
FROM tOrder o LEFT JOIN
Customers c
ON c.ID = o.Customer_id LEFT JOIN
Food f
ON f.ID = o.Food_id LEFT JOIN
Carrier ca
ON ca.ID = o.Carrier_id LEFT JOIN
Waiter w
ON w.ID = o.Waiter_id
If there are no matches, then the orders are still in the results, with NULL for the values in the table with no matches.
Note that this also introduces table aliases, so the query is easier to write and to read.
Based on the following ERD, I'm trying to write a query that displays reservations made directly by customers and include reservation id, reservation date, customer id, customer first name, tour trip id, tour category name, tour trip date
I've been able to include everything in my query except for the tour category name because the TOUR_SITES table is in the way. Is there a way I can join the category name from the TOUR_PACKAGE table without adding any extra columns?
SELECT r.RESERVATION_ID, r.RESERVATION_DATE,
c.CUSTOMER_ID, c.FIRST_NAME,t.TRIP_ID, o.TRIP_DATE/*, P.CATEGORY_NAME*/
FROM CUSTOMER c
INNER JOIN RESERVATION r
ON
r.CUSTOMER_ID=c.CUSTOMER_ID
INNER JOIN TOURTRIP_RESERVATION t
ON
r.RESERVATION_ID=t.RESERVATION_ID
INNER JOIN TOUR_TRIP O
ON
t.TRIP_ID=o.TRIP_ID
WHERE AGENT_ID IS NULL;
Is there a way I can join the category name from the TOUR_PACKAGE table without adding any extra columns?
Sure; just join all tables you need. You don't have to add additional columns (the ones you don't need) into the select column list, but you do have to use the tour_sites table anyway.
Something like this:
select r.reservation_id, r.reservation_date,
c.customer_id, c.first_name,t.trip_id, o.trip_date,
p.category_name
from customer c inner join reservation r on r.customer_id=c.customer_id
inner join tourtrip_reservation t on r.reservation_id=t.reservation_id
inner join tour_trip o on t.trip_id=o.trip_id
--
join tour_sites s on s.tour_siteid = o.tour_siteid --> add
join tour_package p on p.category_id = s.category_id --> this
where agent_id is null;
You need to first join tour_sites with tour_trip on TOUR_SITEID and then join tour_package with tour_sites on category_id to get the tour category_name. You can join left join on tour_sites in case there are no tour sites assigned for a tour trip like a newly added tour_trip.
SELECT r.RESERVATION_ID, r.RESERVATION_DATE, c.CUSTOMER_ID, c.FIRST_NAME,t.TRIP_ID, o.TRIP_DATE,TP.CATEGORY_NAME
FROM CUSTOMER c
INNER JOIN RESERVATION r ON r.CUSTOMER_ID=c.CUSTOMER_ID
INNER JOIN TOURTRIP_RESERVATION t ON r.RESERVATION_ID=t.RESERVATION_ID
INNER JOIN TOUR_TRIP O ON t.TRIP_ID=o.TRIP_ID
LEFT JOIN TOUR_SITES TS ON TS.TOUR_SITEID = O.TOUR_SITEID
INNER JOIN TOUR_PACKAGE TP ON TP.CATEGORY_ID = TS.CATEGORY_ID
WHERE AGENT_ID IS NULL;
I'm looking to see a breakdown of the total dollar business that each vendor has done (indirectly via the distributor) with each customer, where I'm trying not to use the Inner Join Syntax. I basically don't understand the difference between the two outputs produced by the two queries shown below:
Query1
select customers.cust_id, vendors.vend_id, sum(OrderItems.item_price*OrderItems.quantity) as total_business from
(((Vendors left outer join products
on vendors.vend_id = products.prod_id)
left outer join OrderItems
on products.prod_id = OrderItems.prod_id)
left outer join Orders
on OrderItems.order_num = Orders.order_num)
left outer join Customers
on Orders.cust_id = Customers.cust_id
group by Customers.cust_id, vendors.vend_id
order by total_business
I get the following output:
Query2
select customers.cust_id, Vendors.vend_id, sum(quantity*item_price) as total_business from
(((Vendors left outer join Products
on Products.vend_id = Vendors.vend_id)
left outer join OrderItems --No inner joins allowed
on OrderItems.prod_id = Products.prod_id)
left outer join Orders
on Orders.order_num = OrderItems.order_num)
left outer join Customers
on Customers.cust_id = Orders.cust_id
where Customers.cust_id is not null -- THE ONLY DIFFERENCE BETWEEN QUERY1 AND QUERY2
group by Customers.cust_id, Vendors.vend_id
order by total_business
I don't understand how there are only NULL cust_id's associated with the 1st Output when in the 2nd Output we get some non-NULL cust_ids. Why doesn't the 1st Output include these non-NULL cust_id's
Thank You
Query One is joining Vendors and Products incorrectly:
on vendors.vend_id = products.prod_id -- Vend_ID = Prod_ID
Query Two is joining Vendors and Products correctly:
on Products.vend_id = Vendors.vend_id -- Vend_ID = Vend_ID
Once that is fixed, you'll get the same IDs in both queries. Then I suggest you read Dan's answer to understand why what you were trying to do in eliminating INNER JOIN from the query is cancelled out by adding a WHERE filter to a column from the last table in the chain.
When you left join to a table, then filter on that table in the where clause, the join effectively changes to an inner join. The workaround is to apply the filter as a joining condition.
In your second query, all you have to do is is change the word "where" to "and".
How would I preform two inner joins in one query?
Ie: three tables
Invoice
Address
Client
Invoice has a column which references an id in clients. It also has a column which references an address. I need to get both the clients name from the matched table and the address from the matched table. How would I INNER JOIN both tables?
I'll add a few details...
invoice has rows address(references address id), client(references client id), id and notes
client has rows first_name, last_name
address has rows street_name and city
I need to pull up
You can have as many JOIN clauses as you need in the query. Each has an ON clause where you specify the related columns between the joined tables.
SELECT
columns
FROM
invoice
INNER JOIN
address
ON
join_condition
INNER JOIN
client
ON
join_condition
Something like:
SELECT
c.*, i.*, a.*
FROM
invoices i
INNER JOIN
client c
ON
i.clientid = c.clientid
INNER JOIN
address a
ON
a.clientid = c.clientid
WHERE
i.id = 21
Don't forget you only select the fields you require, not * (all).
A sample e.g. based on learning from #Dan Grossman above:
SELECT FILM.TITLE, ACTOR.FIRST_NAME, ACTOR.LAST_NAME FROM ACTOR
INNER JOIN FILM_ACTOR
ON ACTOR.ACTOR_ID = FILM_ACTOR.ACTOR_ID
INNER JOIN FILM
ON FILM_ACTOR.FILM_ID = FILM.FILM_ID
WHERE ACTOR.FIRST_NAME = 'Nick' AND ACTOR.LAST_NAME = 'Wahlberg'