How to map(reference) identical data but different PK? - sql

I'm doing some database data migration.
The problem is the records (ContactsID) has changed - because of PK increment as well as mixed data (I can't just put the SQL result next to each other etc...)
Here is an example
Data in Original table
+-----------+-------------+
| CompanyID | CompanyName |
+-----------+-------------+
| 1 | Facebook |
+-----------+-------------+
In New Database
+-----------+-------------+
| CompanyID | CompanyName |
+-----------+-------------+
| 9 | Facebook |
+-----------+-------------+
I'm having issues when it comes to importing matching records from another table that reference the Data in the original database.
Is there a tool I can use to help me match the records?
Here is my desired result
+-----------+-------------+-----+
| CompanyID | CompanyName | Key |
+-----------+-------------+-----+
| 1 | Facebook | 9 |
+-----------+-------------+-----+
I will use the key import better.

There is join:
select o.CompanyName, o.CompanyID, n.CompanyID
from original o join
newdatabase n
on o.CompanyName = n.CompanyName

Related

How can I convert varchar (1,2,3) to a correlating column values name in SQL Server 2014?

I have an issue with converting a varchar column filled with id's (foreign keys) to another string with names, these names are linked in another table with their correlating id.
Data
x-----x------------------------x
| Id | foreign Keys (varchar) |
x-----x------------------------x
| 1 | 1,2,3 |
| 2 | 2,3,4 |
| 3 | 4 |
x-----x------------------------x
Names
x-----x-----------------x
| Id | Names (varchar)|
x-----x-----------------x
| 1 | Rick |
| 2 | Steven |
| 3 | Charly |
| 4 | Tom |
x-----x-----------------x
Basically I need the values in the table data to UPDATE to a varchar like 'Rick, Steven, Charly'.
I am working in SQL Server 2014, so I can't use the function STRING_SPLIT.
Help would be really appreciated
Thanks

Select unique combination of values (attributes) based on user_id

I have a table that has user a user_id and a new record for each return reason for that user. As show here:
| user_id | return_reason |
|--------- |-------------- |
| 1 | broken |
| 2 | changed mind |
| 2 | overpriced |
| 3 | changed mind |
| 4 | changed mind |
What I would like to do is generate a foreign key for each combination of values that are applicable in a new table and apply that key to the user_id in a new table. Effectively creating a many to many relationship. The result would look like so:
Dimension Table ->
| reason_id | return_reason |
|----------- |--------------- |
| 1 | broken |
| 2 | changed mind |
| 2 | overpriced |
| 3 | changed mind |
Fact Table ->
| user_id | reason_id |
|--------- |----------- |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 3 |
My thought process is to iterate through the table with a cursor, but this seems like a standard problem and therefore has a more efficient way of doing this. Is there a specific name for this type of problem? I also thought about pivoting and unpivoting. But that didn't seem too clean either. Any help or reference to articles in how to process this is appreciated.
The problem concerns data normalization and relational integrity. Your concept doesn't really make sense - Dimension table shows two different reasons with same ID and Fact table loses a record. Conventional schema for this many-to-many relationship would be three tables like:
Users table (info about users and UserID is unique)
Reasons table (info about reasons and ReasonID is unique)
UserReasons junction table (associates users with reasons - your
existing table). Assuming user could associate with same reason
multiple times, probably also need ReturnDate and OrderID_FK fields
in UserReasons.
So, need to replace reason description in first table (UserReasons) with a ReasonID. Add a number long integer field ReasonID_FK in that table to hold ReasonID key.
To build Reasons table based on current data, use DISTINCT:
SELECT DISTINCT return_reason INTO Reasons FROM UserReasons
In new table, rename return_reason field to ReasonDescription and add an autonumber field ReasonID.
Now run UPDATE action to populate ReasonID_FK field in UserReasons.
UPDATE UserReasons INNER JOIN UserReasons.return_reason ON Reasons.ReasonDescription SET UserReasons.ReasonID_FK = Reasons.ReasonID
When all looks good, delete return_reason field.

Filling information from same and other tables in SQL

For my further work I need to create a lookup table where all the different IDs my data has (because of different sources) are noted.
It has to look like this:
Lookup_Table:
| Name | ID_source1 | ID_source2 | ID_source3 |
-----------------------------------------------
| John | EMP_992 | AKK81239K | inv1000003 |
Note, that Name and ID_Source1 are coming from the same table. The other IDs are coming from different tables. They share the same name value, so e.g. source 2 looks like this:
Source2 Table:
| Name | ID |
--------------------
| John | AKK81239K |
What is the SQL code to accomplish this? Im using Access and it doesnt seem to work with this code for source 2:
INSERT INTO Lookup_Table ([ID_Source2])
SELECT [Source2].[ID]
FROM Lookup_Table LEFT JOIN [Source2]
ON [Lookup_Table].[Name] = [Source2].[Name]
It just adds the ID from Source2 in a new row:
| Name | ID_source1 | ID_source2 | ID_source3 |
-----------------------------------------------
| John | EMP_992 | | |
| | | AKK81239K | |
Hope you guys can help me.
You're looking for an UPDATE query, not an INSERT query.
An UPDATE query updates existing records. An INSERT query inserts new records into a table.
UPDATE Lookup_Table
INNER JOIN [Source2] ON [Lookup_Table].[Name] = [Source2].[Name]
SET [ID_Source2] = [Source2].[ID]

Oracle Recursive Select to Find Current ID Associated with a Customer

I have a table that contains the history of Customer IDs that have been merged in our CRM system. The data in the historical reporting Oracle schema exists as it was when the interaction records were created. I need a way to find the Current ID associated with a customer from potentially an old ID. To make this a bit more interesting, I do not have permissions to create PL/SQL for this, I can only create Select statements against this data.
Sample Data in customer ID_MERGE_HIST table
| OLD_ID | NEW_ID |
+----------+----------+
| 44678368 | 47306920 |
| 47306920 | 48352231 |
| 48352231 | 48780326 |
| 48780326 | 50044190 |
Sample Interaction table
| INTERACTION_ID | CUST_ID |
+----------------+----------+
| 1 | 44678368 |
| 2 | 48352231 |
| 3 | 80044190 |
I would like a query with a recursive sub-query to provide a result set that looks like this:
| INTERACTION_ID | CUST_ID | CUR_CUST_ID |
+----------------+----------+-------------+
| 1 | 44678368 | 50044190 |
| 2 | 48352231 | 50044190 |
| 3 | 80044190 | 80044190 |
Note: Cust_ID 80044190 has never been merged, so does not appear in the ID_MERGE_HIST table.
Any help would be greatly appreciated.
You can look at CONNECT BY construction.
Also, you might want to play with recursive WITH (one of the descriptions: http://gennick.com/database/understanding-the-with-clause). CONNECT BY is better, but ORACLE specific.
If this is frequent request, you may want to store first/last cust_id for all related records.
First cust_id - will be static, but will require 2 hops to get to the current one
Last cust_id - will give you result immediately, but require an update for the whole tree with every new record

Unique string table in SQL and replacing index values with string values during query

I'm working on an old SQL Server database that has several tables that look like the following:
|-------------|-----------|-------|------------|------------|-----|
| MachineName | AlarmName | Event | AlarmValue | SampleTime | ... |
|-------------|-----------|-------|------------|------------|-----|
| 3 | 180 | 8 | 6.780 | 2014-02-24 | |
| 9 | 67 | 8 | 1.45 | 2014-02-25 | |
| ... | | | | | |
|-------------|-----------|-------|------------|------------|-----|
There is a separate table in the database that only contains unique strings, as well as the index for each unique string. The unique string table looks like this:
|----------|--------------------------------|
| Id | String |
|----------|--------------------------------|
| 3 | MyMachine |
| ... | |
| 8 | High CPU Usage |
| ... | |
| 67 | 404 Error |
| ... | |
|----------|--------------------------------|
Thus, when we want to get something out of the database, we get the respective rows out, then lookup each missing string based on the index value.
What I'm hoping to do is to replace all of the string indexes with the actual values in a single query without having to do post-processing on the query result.
However, I can't figure out how to do this in a single query. Do I need to use multiple JOINs? I've only been able to figure out how to replace a single value by doing something like -
SELECT UniqueString.String AS "MachineName" FROM UniqueString
JOIN Alarm ON Alarm.MachineName = UniqueString.Id
Any help would be much appreciated!
Yes, you can do multiple joins to the UniqueStrings table, but change the order to start with the table you are reporting on and use unique aliases for the joined table. Something like:
SELECT MN.String AS 'MachineName', AN.String as 'AlarmName' FROM Alarm A
JOIN UniqueString MN ON A.MachineName = MN.Id
JOIN UniqueString AN ON A.AlarmName = AN.Id
etc for any other columns