I am working on a project where I have to solve the following problem.
Goal:
If there are two rows that same the same identifier, but additional data that is different, how can I combine all of that data into one row with individual columns?
Example:
DateBase:
| ID | Rating | Rating Provider|
--------------------------------
| 5055 | A+ | Moodys |
---------------------------------
| 5055 | Bb+ | SNP |
Desired End Result:
| ID | Moodys | SNP |
--------------------
| 5005 | A+ | Bb+ |
I believe you simply need a Pivot -
SELECT *
FROM YOUR_TABLE
PIVOT(MAX(Rating)
FOR Rating_Provider IN (Moodys AS 'Moodys', SNP AS 'SNP'));
Quantnesto, i believe that what you are looking for it's the JOIN function. You have the information in different databases, right?
You SELECT all the fields that you want from the different tables
SELECT a.ID,a.Moodys,B.SNP
FROM DataBase a
JOIN Database b on a.ID = b.ID
And that's it.
There are different kinds of JOIN's, for further information let me know, i can explain each type.
Related
I want to join tables in MS Access in such a way that it fetches only the latest record from one of the tables. I've looked at the other solutions available on the site, but discovered that they only work for other versions of SQL. Here is a simplified version of my data:
PatientInfo Table:
+-----+------+
| ID | Name |
+-----+------+
| 1 | John |
| 2 | Tom |
| 3 | Anna |
+-----+------+
Appointments Table
+----+-----------+
| ID | Date |
+----+-----------+
| 1 | 5/5/2001 |
| 1 | 10/5/2012 |
| 1 | 4/20/2018 |
| 2 | 4/5/1999 |
| 2 | 8/8/2010 |
| 2 | 4/9/1982 |
| 3 | 7/3/1997 |
| 3 | 6/4/2015 |
| 3 | 3/4/2017 |
+----+-----------+
And here is a simplified version of the results that I need after the join:
+----+------+------------+
| ID | Name | Date |
+----+------+------------+
| 1 | John | 4/20/2018 |
| 2 | Tom | 8/8/2010 |
| 3 | Anna | 3/4/2017 |
+----+------+------------+
Thanks in advance for reading and for your help.
You can use aggregation and JOIN:
select pi.id, pi.name, max(a.date)
from appointments as a inner join
patientinfo as pi
on a.id = pi.id
group by pi.id, pi.name;
something like this:
select P.ID, P.name, max(A.Date) as Dt
from PatientInfo P inner join Appointments A
on P.ID=A.ID
group by P.ID, P.name
Both Bing and Gordon's answers work if your summary table only needs one field (the Max(Date)) but gets more tricky if you also want to report other fields from the joined table, since you would need to include them either as an aggregated field or group by them as well.
Eg if you want your summary to also include the assessment they were given at their last appointment, GROUP BY is not the way to go.
A more versatile structure may be something like
SELECT Patient.ID, Patient.Name, Appointment.Date, Appointment.Assessment
FROM Patient INNER JOIN Appointment ON Patient.ID=Appointment.ID
WHERE Appointment.Date = (SELECT Max(Appointment.Date) FROM Appointment WHERE Appointment.ID = Patient.ID)
;
As an aside, you may want to think whether you should use a field named 'ID' to refer to the ID of another table (in this case, the Apppintment.ID field refers to the Patient.ID). You may make your db more readable if you leave the 'ID' field as an identifier specific to that table and refer to that field in other tables as OtherTableID or similar, ie PatientID in this case. Or go all the way and include the name of the actual table in its own ID field.
Edited after comment:
Not quite sure why it would crash. I just ran an equivalent query on 2 tables I have which are about 10,000 records each and it was pretty instanteneous. Are your ID fields (i) unique numbers and (ii) indexed?
Another structure which should do the same thing (adapted for your field names and assuming that there is an ID field in Appointments which is unique) would be something like:
SELECT PatientInfo.UID, PatientInfo.Name, Appointments.StartDateTime, Appointments.Assessment
FROM PatientInfo INNER JOIN Appointments ON PatientInfo_UID = Appointments.PatientFID
WHERE Appointments.ID = (SELECT TOP 1 ID FROM Appointments WHERE Appointments.PatientFID = PatientInfo_UID ORDER BY StartDateTime DESC)
;
But that is starting to look a bit contrived. On my data they both produce the same result (as they should!) and are both almost instantaneous.
Always difficult to troubleshoot Access when it crashes - I guess you see no error codes or similar? Is this against a native .accdb database or another server?
I'm honestly not sure how to title this - so apologies if it is unclear.
I have two tables I need to compare. One table contains tree names and nodes that belong to that tree. Each Tree_name/Tree_node combo will have its own line. For example:
Table: treenode
| TREE_NAME | TREE_NODE |
|-----------|-----------|
| 1 | A |
| 1 | B |
| 1 | C |
| 1 | D |
| 1 | E |
| 2 | A |
| 2 | B |
| 2 | D |
| 3 | C |
| 3 | D |
| 3 | E |
| 3 | F |
I have another table that contains names of queries and what tree_nodes they use. Example:
Table: queryrecord
| QUERY | TREE_NODE |
|---------|-----------|
| Alpha | A |
| Alpha | B |
| Alpha | D |
| BRAVO | A |
| BRAVO | B |
| BRAVO | D |
| CHARLIE | A |
| CHARLIE | B |
| CHARLIE | F |
I need to create an SQL where I input the QUERY name, and it returns any ‘TREE_NAME’ that includes all the nodes associated with the query. So if I input ‘ALPHA’, it would return TREE_NAME 1 & 2. If I ask it for CHARLIE, it would return nothing.
I only have read access, and don’t believe I can create temp tables, so I’m not sure if this is possible. Any advice would be amazing. Thank you!
You can use group by and having as follows:
Select t.tree_name
From tree_node t
join query_record q
on t.tree_node = q.tree_node
WHERE q.query = 'ALPHA'
Group by t.tree_name
Having count(distinct t.tree_node)
= (Select count(distinct q.tree_node) query_record q WHERE q.query = 'ALPHA');
Using an IN condition (a semi-join, which saves time over a join):
with prep (tree_node) as (select tree_node from queryrecord where query = :q)
select tree_name
from treenode
where tree_node in (select tree_node from prep)
group by tree_name
having count(*) = (select count(*) from prep)
;
:q in the prep subquery (in the with clause) is the bind variable to which you will assign the various QUERY values at runtime.
EDIT
I don't generally set up the test case on online engines; but in a comment below this answer, the OP said the query didn't work for him. So, I set up the example on SQLFiddle, here:
http://sqlfiddle.com/#!4/b575e/2
A couple of notes: for some reason, SQLFiddle thinks table names should be at most eight characters, so I had to change the second table name to queryrec (instead of queryrecord). I changed the name in the query, too, of course. And, second, I don't know how I can give bind values on SQLFiddle; I hard-coded the name 'Alpha'. (Note also that in the OP's sample data, this query value is not capitalized, while the other two are; of course, text values in SQL are case sensitive, so one should pay attention when testing.)
You can do this with a join and aggregation. The trick is to count the number of nodes in query_record before joining:
select qr.query, t.tree_name
from (select qr.*,
count(*) over (partition by query) as num_tree_node
from query_record qr
) qr join
tree_node t
on t.tree_node = qr.tree_node
where qr.query = 'ALPHA'
group by qr.query, t.tree_name, qr.num_tree_node
having count(*) = qr.num_tree_node;
Here is a db<>fiddle.
I need to create one master table from 5 tables, the difficulty is that the same column across the tables may have a different name. so for instance
For simplicity I`m just going to give an example for 2 tables
+----+----+
| 1 | 2 |
+----+----+
| PO | P |
| VE | V |
| TE | TE |
| LO | LO |
| IN | |
| D | |
| X | |
| Y | |
| | A |
| | B |
| | C |
+----+----+
so as you can see PO doesn`t have the same column name as the corresponding value in table 2 yet they are the same record. I need to aggregate these 2 tables into one master.
What I did was began with the table that has the most repeated columns and I am trying to merge the other tables into it. When there is a column only found on one table I want the other fields to display null. Also I don't want any duplicates. Hope someone can help me out!
Cheers
yet they are the same record.
No, they are not.
They could, however, represent different views of the same business entities. To "merge" them you must first specify what the JOIN criterion between them shall be.
Given it is
one.PO = two.P.
Then you must write a SQL statement like
SELECT one.PO AS ID,
one.VE,
/*same for TE, LO, IN, D, X, Y, */
two.A,
two.B,
two.C
INTO t_what_the_frak_the_new_table_shall_be_called
FROM t_what_the_frak_table_1_is_called AS one,
JOIN t_what_the_frak_table_2_is_called AS two
ON one.PO = two.P;
GO
I have two (linked) sql servers with basically the same setup but they differ in the content. What I want to do is take 2 tables (one from each server) and merge them, so that there are no duplicates ID (e.g., no duplicate fname) and that the the count are added together
They may look like
SERV1.DB1.dbo.Table:
| fname | count |
----------------------
| 'file1.txt' | 10 |
| 'file2.txt' | 5 |
| 'file3.txt' | 35 |
SERV2.DB2.dbo.Table:
| fname | count |
----------------------
| 'file1.txt' | 40 |
| 'file2.txt' | 150 |
And I want to write a select that outputs
| fname | count |
----------------------
| 'file1.txt' | 50 |
| 'file2.txt' | 155 |
| 'file3.txt' | 35 |
I don't want a join and a union doesn't merge them the way I want.
edit
It needs to be case-insensitive as the fname may (read: will) vary in case
fname has different collations (it's a no problem but worth mentioning)
I get these two tables by doing a similar select on each server. I could create temporary tables but I'd prefer if I didn't have too.
You can do it easly with a JOIN
SELECT table1.fname fname, table1.Count + table2.count Count
FROM SERV1.DB1.dbo.Table table1
FULL OUTER JOIN SERV2.DB2.dbo.Table table2 ON table1.fname=table2.fname
EDIT: case-sensitive/-insensitive depends on the column collation
This is my own recommendation, based on giammin's answer:
SELECT
COALESCE(t1.fname,t2.fname) fname,
COALESCE(t1.Count,0) + COALESCE(t2.count,0) Count
FROM
SERV1.DB1.dbo.Table t1
FULL OUTER JOIN
SERV2.DB2.dbo.Table t2
ON t1.fname=t2.fname
which ensures that all fname values from both tables appear in the result, even those that only appear in SERV2's table.
I've created a form in PHP that collects basic information. I have a list box that allows multiple items selected (i.e. Housing, rent, food, water). If multiple items are selected they are stored in a field called Needs separated by a comma.
I have created a report ordered by the persons needs. The people who only have one need are sorted correctly, but the people who have multiple are sorted exactly as the string passed to the database (i.e. housing, rent, food, water) --> which is not what I want.
Is there a way to separate the multiple values in this field using SQL to count each need instance/occurrence as 1 so that there are no comma delimitations shown in the results?
Your database is not in the first normal form. A non-normalized database will be very problematic to use and to query, as you are actually experiencing.
In general, you should be using at least the following structure. It can still be normalized further, but I hope this gets you going in the right direction:
CREATE TABLE users (
user_id int,
name varchar(100)
);
CREATE TABLE users_needs (
need varchar(100),
user_id int
);
Then you should store the data as follows:
-- TABLE: users
+---------+-------+
| user_id | name |
+---------+-------+
| 1 | joe |
| 2 | peter |
| 3 | steve |
| 4 | clint |
+---------+-------+
-- TABLE: users_needs
+---------+----------+
| need | user_id |
+---------+----------+
| housing | 1 |
| water | 1 |
| food | 1 |
| housing | 2 |
| rent | 2 |
| water | 2 |
| housing | 3 |
+---------+----------+
Note how the users_needs table is defining the relationship between one user and one or many needs (or none at all, as for user number 4.)
To normalise your database further, you should also use another table called needs, and as follows:
-- TABLE: needs
+---------+---------+
| need_id | name |
+---------+---------+
| 1 | housing |
| 2 | water |
| 3 | food |
| 4 | rent |
+---------+---------+
Then the users_needs table should just refer to a candidate key of the needs table instead of repeating the text.
-- TABLE: users_needs (instead of the previous one)
+---------+----------+
| need_id | user_id |
+---------+----------+
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 1 | 2 |
| 4 | 2 |
| 2 | 2 |
| 1 | 3 |
+---------+----------+
You may also be interested in checking out the following Wikipedia article for further reading about repeating values inside columns:
Wikipedia: First normal form - Repeating groups within columns
UPDATE:
To fully answer your question, if you follow the above guidelines, sorting, counting and aggregating the data should then become straight-forward.
To sort the result-set by needs, you would be able to do the following:
SELECT users.name, needs.name
FROM users
INNER JOIN needs ON (needs.user_id = users.user_id)
ORDER BY needs.name;
You would also be able to count how many needs each user has selected, for example:
SELECT users.name, COUNT(needs.need) as number_of_needs
FROM users
LEFT JOIN needs ON (needs.user_id = users.user_id)
GROUP BY users.user_id, users.name
ORDER BY number_of_needs;
I'm a little confused by the goal. Is this a UI problem or are you just having trouble determining who has multiple needs?
The number of needs is the difference:
Len([Needs]) - Len(Replace([Needs],',','')) + 1
Can you provide more information about the Sort you're trying to accomplish?
UPDATE:
I think these Oracle-based posts may have what you're looking for: post and post. The only difference is that you would probably be better off using the method I list above to find the number of comma-delimited pieces rather than doing the translate(...) that the author suggests. Hope this helps - it's Oracle-based, but I don't see .