Trying to select the Match Table and convert the ID's into the Schools name, but right now I can only get one row to work at a time. What would my select look like instead?
select Match.ID, School, GuestTeamID from Match
inner join Team on team.id = match.HomeTeamID
Match Table
+------------+------------+-------------+
| ID | HomeTeamID | GuestTeamID |
+------------+------------+-------------+
| 1 | 1 | 2 |
| 2 | 3 | 4 |
+------------+------------+-------------+
Team Table:
+----+----------+
| ID | School |
+----+----------+
| 1 | School A |
| 2 | School B |
| 3 | School C |
| 4 | School D |
+----+----------+
Join Team table twice with Match table to fetch school name.
Try this:
SELECT M.ID, t1.School AS HomeSchool, t2.School AS GuestSchool
FROM MATCH m
INNER JOIN Team t1 ON t1.id = m.HomeTeamID
INNER JOIN Team t2 ON t2.id = m.GuestTeamID;
Related
I've got the following tables: person (id), person_agency (person_id, agency_id) and agency(id, type)
this is my query:
select p.id, a.id from person p
left join person_agency pa on p.id = pa.person_id
left join agency a on pa.agency_id = a.id
where a.type = 'agency_type1'
However, with the query I get only the persons who have a relation with an agency of "agency_type1". Instead, I would like to get a list of ids of ALL persons with ids of agencies, where the relation exists and null where it doesn't. I tried naive outer joins but it did not work.
For this content of the tables:
Person:
+-------+
| id |
+-------+
| 1 |
| 2 |
| 3 |
| 4 |
+-------+
Person_agency:
+-----------+-----------+
| person_id | agency_id |
+-----------+-----------+
| 1 | 1 |
| 1 | 2 |
| 2 | 4 |
| 4 | 5 |
+-----------+-----------+
Agency:
+--------+------------------+
| id | type |
+--------+------------------+
| 1 | agency_type1 |
| 2 | some_other_type |
| 3 | agency_type1 |
| 4 | agency_type1 |
| 5 | some_other_type |
+--------+------------------+
I receive the folloing output of my query:
+----------+------+
| p.id | a.id |
+----------+------+
| 1 | 1 |
| 2 | 4 |
+----------+------+
The desired output would be:
+----------+------+
| p.id | a.id |
+----------+------+
| 1 | 1 |
| 2 | 4 |
| 3 | null |
| 4 | null |
+----------+------+
It looks like you don't want to distinguish between an agency which is missing and an agency which is present but the wrong type. So you would want a regular JOIN not a LEFT JOIN for the pa/a pair, and also want to filter out the unwanted type directly on that join. Then you want to do a LEFT JOIN from person to the results of that just-described join.
select p.id p_id, a.id a_id from person p
left join (person_agency pa join agency a on pa.agency_id = a.id and a.type='agency_type1')
on p.id = pa.person_id;
p_id | a_id
------+--------
1 | 1
2 | 4
3 | (null)
4 | (null)
The parenthesis around the join pair are not necessary but I find they make it clearer.
If one person is associated to multiple agencies of the correct type, all of them will be shown. I assume this is what you want, although it was not a scenario covered in your example data.
Try to change left join
to
join (inner join).
I'm trying to join my users table with my jobs table based on a mapping table users_jobs:
Here is what the users table looks like:
users
|--------|------------------|
| id | name |
|--------|----------------- |
| 1 | Ozzy Osbourne |
| 2 | Lemmy Kilmister |
| 3 | Ronnie James Dio |
| 4 | Jimmy Page |
|---------------------------|
jobs table looks like this:
|--------|-----------------|
| id | title |
|--------|-----------------|
| 1 | Singer |
| 2 | Guitar Player |
|--------------------------|
And users_jobs table looks like this:
|--------|-------------|-------------|---------------|-------------|
| id | user_id | job_id | column3 | column4 |
|--------|-------------|-------------|---------------|-------------|
| 1 | 1 | 1 | 0 | 1 |
| 2 | 2 | 1 | 1 | 0 |
| 3 | 3 | 1 | 0 | 1 |
| 4 | 4 | 2 | 1 | 0 |
|----------------------|-------------|---------------|-------------|
For example, let's say the ozzy does a query.
Here is what should expect:
|--------|------------------|------------|--------- |
| id | name | column3 | column4 |
|--------|----------------- |------------|----------|
| 1 | Ozzy Osbourne | 0 | 1 |
| 2 | Lemmy Kilmister | 1 | 0 |
| 3 | Ronnie James Dio | 0 | 1 |
|---------------------------|------------|----------|
Basically, he can only see the job in which he is registered (role) and the users included.
I tried to do this:
SELECT u1.*, uj1.colum3, uj1.column4
FROM users AS u1
JOIN users_jobs AS uj1 ON uj1.user_id = 1
JOIN jobs AS j1 ON j1.id = up1.job_id
WHERE uj1.job_id = 1
Any help would be great!
Looks like you need INNER JOIN Try this :
select u.id, u.column3 , u.column4 from users u
inner join user_jobs uj on u.id=uj.user_id
inner join jobs j on j.id=uj.job_id
where uj.job_id=1;
If you need by certain user_id
select u.id, u.column3 , u.column4 from users u
inner join user_jobs uj on u.id=uj.user_id
inner join jobs j on j.id=uj.job_id
where uj.job_id=1
and u.id=1;
I found a solution.
Using #stackFan approach adding an EXISTS clause to make sure that the user is in.
SELECT u.id, u.column3 , u.column4
FROM users u
INNER JOIN user_jobs uj on u.id = uj.user_id
INNER JOIN jobs j on j.id = uj.job_id
WHERE uj.job_id = <job-ID>
AND
EXISTS (
SELECT *
FROM users_jobs AS uj
WHERE uj.job_id = <job-ID>
AND uj.user_id = <user-ID>
);
Try LEFT JOIN. It will display all users, whether they have job or not.
SELECT u.id, u.name, uj.colum3, uj.column4
FROM users AS u
LEFT JOIN users_jobs uj ON uj.user_id = u.id
LEFT JOIN jobs j ON j.id = uj.job_id
is it possible if i want to do INNER JOIN only if the record exist on the 2nd table if not then dont join?
this is my table
User table
+--------+--------------+
| id | name |
+--------+--------------+
| 1 | John |
+--------+--------------+
| 2 | Josh |
+--------+--------------+
House table
+--------+-------------+--------------+
| id | owner_id | house_no |
+--------+-------------+--------------+
| 1 | 1 | 991 |
+--------+-------------+--------------+
this is my INNER JOIN query
SELECT h.owner_id, u.name, h.house_no FROM user u
INNER JOIN house h on u.id = h.owner_id
WHERE u.id = :id
it will return this result if id = 1
+--------+--------------+--------------+
| id | name | house_no |
+--------+--------------+--------------+
| 1 | John | 991 |
+--------+--------------+--------------+
but if i run with id = 2 no result returned.
what i want to do right now is it still return the result even when no data exist for id = 2 in table house
Use a left outer join instead.
SELECT u.id, u.name, h.house_no FROM user u
LEFT OUTER JOIN house h on u.id = h.owner_id
WHERE u.id = :id
The resulting record will be:
+--------+--------------+--------------+
| id | name | house_no |
+--------+--------------+--------------+
| 2 | Josh | null |
+--------+--------------+--------------+
I have to make sortable table like this:
Sortable table:
building_id | building_age | title |
-------------------------------------------------
1 | 100 | New york buil |
2 | 50 | House 1 |
3 | 50 | House 10 |
From these tables:
Building Table:
building_id | building_age | building_type_1_FK | building_type_2_FK
---------------------------------------------------------
1 | 100 | null | 1
2 | 50 | 1 | null
3 | 50 | 2 | null
building_type_1:
type_id | title | diff1 |
-------------------------------------------------
1 | New york buil| blablabla |
building_type_2:
building_id | title |
----------------------------
1 | House 1 |
2 | House 10 |
3 | House 500 |
While joining these tables I get several title columns where one of them is not null. Is there any way to sort by title and select top 10 results without fetching all the data and then sorting in the app?
p.s.. I know that in general this architecture is not good, but I can't change it.
Yes. You want to do a left outer join to the two tables, and then bring the results together:
select b.building_id, b.building_age, coalesce(bt1.title, bt2.title) as title
from building b left outer join
building_type_1 bt1
on b.building_type_1_FK = bt1.type_id left outer join
building_type_2 bt2
on b.building_type_2_FK = bt2.building_id;
To get the top 10 results in Oracle:
select *
from (select b.building_id, b.building_age, coalesce(bt1.title, bt2.title) as title
from building b left outer join
building_type_1 bt1
on b.building_type_1_FK = bt1.type_id left outer join
building_type_2 bt2
on b.building_type_2_FK = bt2.building_id
order by title
) b
where rownum <= 10;
Hopefully this will be an easy question!
I have two tables, a 'client(s)' table and an individual 'names' table. The basis is that a client can have one or two(max) names. I structured them like this so that each 'name' can have a different title. The tables are:
clients
+------------+-------------+------------+
| clientID | nameID1 | nameID2 |
+------------+-------------+------------+
| 1 | 1 | 2 |
| 2 | 3 | |
| 3 | 4 | |
+------------+-------------+------------+
names
+------------+-------------+------------+------------+
| nameID | surname | initials | titleID |
+------------+-------------+------------+------------+
| 1 | Banks | P | 1 |
| 2 | Smith | W | 2 |
| 3 | Wilson | BT | 2 |
| 4 | Jefferson | JP | 3 |
+------------+-------------+------------+------------+
Where titleID is retrieved from...
titles
+------------+-------------+
| titleID | titleName |
+------------+-------------+
| 1 | Mr |
| 2 | Mrs |
| 3 | Miss |
+------------+-------------+
So for instance clientID = 1 is Mr P Banks '&' Mrs W Smith
The problem is I'm not familiar with querying to get that answer above.
I cannot try:
SELECT
clientID, names.surname, names.initials, titleName
FROM clients, names, titles
WHERE titleID = titleID AND
NameID1 = nameID AND
NameID2 = nameID
How do I correctly join the tables in a query to find, e.g.,
clientID 1 = Mr P Banks '&' Mrs W Smith
You need to join to the Names (and Titles) table twice, once for nameID1, and once for nameID2. I've assumed that the client must have at least one name hence nameID1 is INNER JOIN, and since namedID2 is optional (nullable) it is LEFT OUTER JOIN.
SELECT c.clientID, n1.surname, n1.initials, t1.titleName, n2.surname, n2.initials, t2.titleName
FROM clients c
INNER JOIN names n1 ON nameID1 = n1.nameID
INNER JOIN titles t1 ON n1.titleID = t1.titleID
LEFT OUTER JOIN names n2 ON nameID2 = n2.nameID
INNER JOIN titles t2 ON n2.titleID = t2.titleID