I have two tables...
groupid membership_list managerid
-------------------------------------
0 /0//1//2/ 2
1 /2/ 2
userid username
------------------
0 ben
1 tom
2 dan
I'd like to display a table to for example the user 'ben' that is a list of the groups they are a member of that looks like this...
groupid membership_list managername
---------------------------------------
0 /0//1//2/ dan
.. so basically replacing 'manager_id' with the username for that id. I've been hacking away at this but I can't work it out - my SQL skills are clearly a bit lacking - how can I do this?
SELECT groupid, membership_list, managerid FROM blah WHERE membership_list LIKE '%/?/%'
... is about as far as I've got.
SELECT t1.groupid, t1.membership_list, t2.username
FROM table1 t1
INNER JOIN table2 t2 ON t1.managerid = t2.userid
That should do it. Or am I missing something here??
SELECT A.groupid, A.membership_list, B.managername FROM table1 A, table2 B WHERE A.managerid = B.userid and membership_list LIKE '%/?/%'
you need to break out membership_list column into a new table:
changed table: Groups
groupid
managerid
table users
userid
username
new table: UserGroups
groupid
userid
you can then do this:
SELECT
*
FROM Users u
INNER JOIN UserGroups ug On u.userid=ug.userid
INNER JOIN Groups g ON ug.groupid=g.groupid
WHERE u.Name='Ben'
to find all of Ben's groups.
If you don't want to modify your tables, you will need a split function that will convert the multiple values in membership_list into rows. You have not mentioned the actual database you are working on and a split function is dependent on knowing that.
Related
Here is my table in my database:
table1 table2
---------|-------- --------|
UserID |Type UserID |
---------|-------- --------|
user1 |Busy user1 |
user2 |Free user2 |
user3 |Free user3 |
user4 |Busy user4 |
I would like to select all the userID from table1 where the Type=Free. The only correlation from one table to another is that they have the same UserID in both tables.
What I have so far is :
SELECT UserID
FROM Data.Users
INNER JOIN Data.UserType
ON Data.Users.UserID=Data.UserType.UserID
This only gives me back ALL the userID where the UserID from table 1 = UserID from table 2.
I would like to be able to make it also check for the user type. Something like
SELECT Username FROM Data.Users WHERE TABLE2.UserID = TABLE1.UserID AND
TABLE2.UserType = "free"
I'm new to SQL so I don't think I'm Googling the right thing as well
So your query is working you just need to filter it:
SELECT Data.Users.Name
FROM Data.Users
INNER JOIN Data.UserType
ON Data.Users.UserID=Data.UserType.UserID
WHERE Data.UserType.Type = 'Free'
You have to ensure you are first selecting the data that you want, in this case "Type". So that's all we need to be concerned with when selecting information. However, for illustration purposes (and general good etiquette) lets also select the userID, but we'll take this from table1.
So we want to select Type from Table 2, and UserID from table 1, but where UserID is the same on both tables.
To do what we need to do the following:
SELECT two.Type, one.UserID FROM table2 two INNER JOIN table1 one ON two.UserID = one.UserID
This selects the information, from table2 and we assign it the reference two. Then we join table1 and assign the reference one. We can then grab the requested information in the select using the references we assigned, whilst also ensuring the data is joined where the two tables have identical values.
The above example will select all values where the userID's match, and is used for illustration purposes. Then, to narrow it down, all you have to do is specify the WHERE value on top of this. So:
SELECT two.Type, one.UserID FROM table2 two INNER JOIN table1 one ON two.UserID = one.UserID WHERE two.Type = "Free"
I have two tables one is teacher and another is Department which is mentioned below.
Teacher Table
Id Name
1 xyz
2. Gjd
3. Dftr
4 dhdk
Department Table
Id Name EMPID
1 SQL. 2
2. PHP. 4
3. JAVA. 1
4 PEARL. 5
QUESTION
i want those records of teacher which are not link with any Department.
you can use following statement using left join then filter Teacher that not matched
SELECT t.*
FROM Teacher t
left join Department d on d.EMPID = t.Id
where d.id is null
SELECT * FROM teachers WHERE
id NOT IN (SELECT DISTINCT EMPID FROM departments) ;
Hope this helps.!!
you can do it by inner query..
select * from teacher where id not in (select empid from department);
I may be overthinking this but I have not managed to figure it out or find a solution, so I'm hoping for a pointer in the right direction. I tried using the Select ColumnA AS Column B etc but it's not doing what I want.
I have 2 tables, scenario examples below
Table 1 (Vehicle)
VehicleID (001)
VehicleMake (Ford)
VehicleModel (Falcon)
VehicleExCleanEmpID (005)
VehicleIntCleanEmpID (003)
Table 2 (Employee)
EmpID (005)
EmpName (Dave)
The scenario being that a vehicle is cleaned internally or externally by any one of a pool of employees shown by the relevant ID in the Vehicles table.
I want to show in a query VehicleID, InsideCleanName, ExternalCleanName rather than showing the employee's ID.
So end up with results similar to this
VehicleID InsideCleanName ExternalCleanName
------------------------------------------------
001 Bob Dave
002 Sue Dave
003 John Sid
Thanks for any tips and or help
THat seems like a pretty simple query with two inner joins to the Employee table - something like this:
SELECT
v.VehicleId,
InsideCleanName = e1.EmpName,
ExternalCleanName = e2.EmpName
FROM
dbo.Vehicle v
INNER JOIN
dbo.Employee e1 ON v.VehicleIntCleanEmpId = e1.EmpID
INNER JOIN
dbo.Employee e2 ON v.VehicleExCleanEmpId = e2.EmpID
Joining to the Employee e1 table is giving you the employee who was responsible for the inside cleaning, while joining a second time, to Employee e2 gives you the one responsible for the external cleaning.
Join the two table with EmpId and select the columns you want similar to the code below:
select column1, column2 from table1 inner join table2 on table1.EmpId = table2.EmpId
Today I have a final Exam. I approved, happily :D but one of the problems is really blowing my mind.
I need help, so I can rest in peace.
THE PROBLEM
We have a table "People"
(PK)id | name | fatherID
---------------------
1 | gon | 2
2 | cesar| 6
3 | luz | 2
4 | maria| 5
5 | diego| 6
6 | john | -
this is only an example of data.
This table has a relation with itself, on table fatherId(FK) with table id(PK)
I need to do a query that show me 2 columns, in one the name of a person, and in the another one, his/her cousin.
Pretty simple until here, right?
The problem is that I have some restrictions
ONLY ANSI allowed. NO T-sql, or another one. Also, ANSI 99 standard, not 2003 or higher
subquerys are not allowed. And the worst:
NO relations repeated.
For example, considering in this example, gon and maria are cousins.
If I show, gon | maria in the results, I can't show maria | gon.
SO, how I can do this?
Is really burning my head.
What I tried?
Well, the big problem was in the last requisite, the repetition of data. Ignoring that, I put this on my exam (knowing is wrong..)
select p3.name as OnePerson, p4.name as Cousin
from
people p1
inner join people p2 on p1.fatherid = p2.fatherid and p1.id != p2.id
inner join people p3 on p1.id = p3.fatherid
inner join people p4 on p1.id = p4.fatherid
of course, this is not solving the last requeriment, and I have a 4 in the test(we pass with 4) but anyway, my head is burning. So please, help me!
Another options explored
one of my friends, that also had the same exam said me
"Well, considering every relation is duplicated, I can use top
count(*) and an order by and get the half correct"
but.. Top is not ANSI!
You can add to your query WHERE p3.id < p4.id. This will eliminate duplicate results like gon | maria and maria | gon.
SELECT T1.id , T2.id FROM
(
SELECT A.id,A.fid FROM family A
WHERE a.fid IN
(
SELECT id FROM family
WHERE fid IN (SELECT id FROM family WHERE fid IS NULL)
)
)T1
JOIN
(
SELECT A.id,A.fid FROM family A
WHERE a.fid IN
(
SELECT id FROM family
WHERE fid IN (SELECT id FROM family WHERE fid IS NULL)
)
)T2
ON t1.fid<>t2.fid
AND t1.id<t2.id
This will give you the results in format you want.
SELECT TAB1.ID,TAB2.ID
FROM
(
SELECT * FROM people T1
WHERE fatherID IN ( SEL T1.ID FROM people T1 INNER JOIN people T2
ON( T1.id=T2.fatherID) WHERE T1.fatherID IS NOT NULL GROUP BY 1) ) TAB1
INNER JOIN
(
SELECT * FROM people T1
WHERE fatherID IN ( SEL T1.ID FROM people T1 INNER JOIN people T2
ON( T1.id=T2.fatherID)WHERE T1.fatherID IS NOT NULL GROUP BY 1) ) TAB2
ON( TAB1.fatherID<>TAB2.fatherID)
GROUP BY 1,2
WHERE TAB1.ID <TAB2.ID;
it's been a while since I used SQL so I'm asking sorry if it's too easy.
I have to select all the skills that a user has, so I have three tables.
User (id, name)
Skills (id, name)
User_skills (id_user, id_skill)
If the user1 has 2 skills; for example Hibernate (id 1) and Java (id 2)
and the user2 has 1 skill; Java (id 1)
Passing 1 and 2, I want to retrieve users that have both.
With the IN() function I get all the users that have at least one of the skills, but I want to filter them out!
Thanks to all in advance
If one skill can only be assigned exactly once to a user (i.e. (id_user, id_skill) is the PK for the user_skills table), then the following will do what you want:
SELECT id_user
FROM user_skills
WHERE id_skill IN (1,2)
GROUP BY id_user
HAVING count(*) = 2
Join to the association table user_skills twice, putting the skill ID in the on clause of each join:
select u.*
from user u
join user_skills us1 on us1.id_user = u.id and us1.id_skill = 1
join user_skills us2 on us2.id_user = u.id and us2.id_skill = 2
By using join (and not left join) this query requires the user have both skills
SELECT name FROM user as u
WHERE
EXISTS( SELECT 1 FROM User_skills WHERE id_user=u.id AND id_skill=1 )
AND EXISTS( SELECT 1 FROM User_skills WHERE id_user=u.id AND id_skill=2 )