I have 3 tables.
Table Alpha:
ID NAME
____ _____
Table Beta:
NAME GOALS
_____ _______
Table Charlie:
NAME SCHOOL
_____ _________
I want a table
ID NAME GOALS SCHOOL
______________________________
Note:
ID's are not unique. so for each ID there may be many names. The issue right now is I get MANY MANY duplicate rows when i use inner joins or left joins. Do help (SQL Newbie)
Thank you :))
Name is your foreign key, so if there are two of the same name in Beta, or Charlie, it's going to duplicate the Alpha rows.
What you need to decide is how you'll aggregate the values from the other tables.
You'll probably want the sum of goals for each name, but school, you'll have to pick one. Otherwise you'll have duplicate rows for each school per name.
So, if alpha is
1 John
2 Sue
And Charlie is
John UHT
John MIT
Sue MIT
You'll end up with
1 John UHT
1 John MIT
2 Sue MIT
If Beta has
John 4
John 5
It gets worse. Now John is going to show up 4 times.
So, you'll need to apply aggregate methods. Then do
... Group By Name
Related
I am trying to query in MS SQL and I can not resolve it. I have a table employees:
Id Name Surname FatherName MotherName WifeName Pincode isChild
-- ------- ------- ---------- ---------- -------- ------- -------
1 John Green James Sue null 101011 1
2 Michael Sloan Barry Lilly null 101011 1
3 Sally Green Andrew Molly Jemi 101011 1
4 Barry Sloan Soul Paul Lilly 101011 0
5 James Green Ned White Sue 101011 0
I want a query that selects rows where the father name and mother name of child matches with name and wife name. For the example table, where I want to return the result of rows where father and mother name matches the name and wife name column. For eg. id=1, where John's father name James and mother name Sue matches with id 5 which returns James as first name and Sue as wife name. So my query should return (this is my expected result)
Id Name Surname FatherName MotherName WifeName Pincode isChild
-- ------- ------- ---------- ---------- -------- ------- -------
5 James Green Ned White Sue 101011 0
4 Barry Sloan Soul Paul Lilly 101011 0
I tried with the below query but it checks for James only. How to change my query so that it checks all the names and returns the expected result.
select * FROM employees
where first_name like '%James%'
and wife_name like '%Sue%'
and pincode=101011;
Any tips on this will be really helpful. I am new to joins, need help on writing self join to get the result.
…
select *
from thetable as p -- the parent/father
where exists -- with one child at least
(
select *
from thetable as c
where c.fathername = p.name
and c.mothername = p.wifename
-- lastname?
)
Too long for a comment, but also not intended as a slam against what you are working with. Please take as constructive criticism.
Aside from VERY POOR DESIGN on the table content, getting that corrected before you get too deep into whatever you are working should be done first. A more typical design might be having a table of people. Now, to get the relationships you could do a couple ways. One is that on each individual person's record, you add 2 additional IDs. FatherID, MotherID. These IDs would join directly back to the child vs hard strings to match against. Take a surname like Smith or Jones. Then, look at the many instances of a "John Smith" may exist, yes a lot, and lower probability of finding a matching wife's name of Sue, Mary or whatever else name. But even that could lead to multiple possibilities. Yes, you are adding a PIN, but even a computer can generate a random pin of 1234.
By having the IDs, there is NO ambiguity of who the relationship is with.
If the data were slightly altered to something like
Id Name Surname FatherID MotherID SpouseID
-- ------- ------- ---------- ---------- --------
1 John Green 5 6 null
2 Michael Sloan 4 3 null
3 Lilly Sloan null null 4
4 Barry Sloan null null 3
5 James Green 9 10 6
6 Sue Green 7 8 5
7 Bill Jones null null 8
8 Martha Jones null null 7
9 Brian Green null null 10
10 Beth Smith-Green null null 9
So, in this modified example, you can see right away that ID#1 John Green has parents of Father (ID#5) is James and Mother (ID#6) is Sue. But even from this, James is a child to Father (ID#9) Brian and Mother (ID#10) Beth. This scenario is showing to a grand-parent level capacity and that each of James and Sue are also children but to their respective parents. Sue's parents of the Jones surname.
For Michael Sloan, parents of #4 Barry, and #3 Lilly.
And I additionally added a spouse ID. This prevents redundancy of people's names copied all over. Then you can query based on the child's parent's respective IDs to find out vs a hopeful name LIKE guess.
So, even though not solving a relatively simple query, fixing the underlying foundation of your database and is relations will, long-term, help ease your querying in the future.
Try this:
SELECT
T2.*
FROM Employee T1
JOIN Employee T2 ON T2.Name = T1.FatherName
AND T2.WifeName = T1.MotherName
I'm having trouble with a LIKE function in proc sql.
PROC SQL;
CREATE TABLE NAMES_IDS AS
SELECT DISTINCT
T1.*
,T2.NAMES
,T2.NAME_ID
FROM WORK.table1 T1
LEFT JOIN data.table2 T2 ON T2.NAMES like T1.NAMES1
;QUIT;
I have several names in t2, lets say for example theres John 1, John 2, John 3, John 4, etc and in t1.Names1 there is %John%
proc sql is just pulling in the first match, John 1 and its associated ID, and applying it to all the data in T1, instead of duplicated a match for all matching names (this is what I want to achieve).
So the end table would have something like
COLUMN A COLUMN B
John John 1
John John 2
John John 3
John John 4
But instead, what I get is:
COLUMN A COLUMN B
John John 1
John John 1
John John 1
John John 1
Hopefully this makes some sort of sense...
I think I figured it out, I added TRIM to my code and I guess there may have been some erroneous spaces somewhere because that seems to fix my issue. Thanks for your responses!
I have three tables as below:
First Table Second Table Third Table
Name PIN Id City City_id
David 1948 1 Roma 3
Susan 1245 2 Berlin 2
Jack 1578 3 New York 3
Hans 1247 2
Rose 8745 1
I want to merge first and second table according to third table. Result will be: Person
Name PIN City
David 1948 New York
Susan 1245 Berlin
Jack 1578 New York
Hans 1247 Berlin
Rose 8745 Roma
Firsty I can merge second and third table and then merge the result table with first table but I want to solve this problem without a medium table. How can I handle this? How can I combine first table's rows in sequence with a specified row in second table according to third table?
You would need a fourth table, PersonCity, with PersonID and CityID to link together. Think of relational databases like a grid (spreadsheet, roads). If you're going North and the street you want to get on is parallel (think |^| |^|) you're gonna need to use a different road that links the two. Currently, you have no such path.
The short answer is that your tables are not adequate for the task, what you need is along the lines of:
Table_1 Table_2 Table_3
Id Name PIN Id City Name_id City_id
1 David 1948 1 Roma 1 3
2 Susan 1245 2 Berlin 2 2
3 Jack 1578 3 New York 3 3
4 Hans 1247 4 2
5 Rose 8745 5 1
Then you can do your query as follow:
SELECT T1.Name, T1.PIN, T2.City
FROM Table_1 T1 LEFT JOIN Table_3 T2 ON T1.Id = T3.Name_id
LEFT JOIN Table_2 ON T3.City_id = T2.Id
ORDER BY T1.Name
Or you could ORDER BY City, name
I have good news and bad news.
The good news, Given the tables the way they were originally specified, in Oracle, this will give you something that looks like what you are asking:
---
--- Pay attention, This looks right but it is not!
---
select name,pin,city from
( select name,pin,rownum rn from first ) a,
( select city,id from second) b,
( select id,rownum rn from third ) c
where
a.rn=c.rn AND
b.id=c.id;
NAME PIN CITY
-------------------- ---- --------------------
Rose 8745 Roma
Susan 1245 Berlin
Hans 1247 Berlin
David 1948 New York
Jack 1578 New York
The bad news is this does not really work and is cheating. You will get results but they may not be what you would expect and they won't necessarily be consistent.
The database orders records in its own order. If you don't specify an order by clause, you get what they give you, which may not be what you want. This is cheating because Oracle does not REALLY support using rownum in this way because you can't bet on what you will get. This won't work in most other databases.
The only correct way is what #daShier gave, where you have to add something, say, ID, to allow connecting the rows in the order you want.
I have tbl1 Structured like this
Name Type
====== =====
John 1
David 1
Jane 2
William 3
Alex 2
Ryan 1
And tbl2 structured like this
Index Type Job
1 1 Clean
2 1 Wash
3 2 Carry
4 2 Package
5 3 Sell
I would like to join record with matched Type, but each record in tbl1 only join once with one record in tbl2
Ie:
If
John is joined with Clean then David must be joined with Wash. Or if John is joined with Wash then David must be joined with Clean.
Doesn't matter if David is joined with Wash or Clean , I only need them to be joined with record that match the criteria and be joined ONCE.
I will make sure for each Type in 'tbl1' there will be equivalent amount of record in 'tbl2'
I mainly work on MS Access so Query on this environment would be the best~ Thank you all for reading.
Best regards
Try below query.
select name, (select TOP(1) job from tbl2 where tbl1.type = tbl2.type) from tbl1
Hope it help
I have 2 tables e.g.
First table
ID Value
1 Apple
2 Orange
3 Banana## ...
Second Table
PERSON FRUIT
Amy 1
Peter 2
Charlie 1,2
Dick 2,3
I would like to for example save what fruits the users have in just one column. So that when I call out what Charlie wants, I can somehow receive and output of Apple, Orange; and for Dick - Orange, Banana etc.
I am not really sure where to start on achieving this. Is it possible to do it purely in an SQL select statement alone?
You could implement a link table. For example.. you have a Fruit Table, which stores all the unique fruits, and you have a Person table that stores all unique people.
So you should create a third table that links unique fruits to people for example...
ID FRUIT PERSON
1 1 1
2 1 2
3 2 1
etc... then a select on the link table with the person ID, would bring up all the fruits that person likes.