I'm working on project that has data warehouse implemented. The fact table has datetime stored in the format:
2015-01-31 23:10:49.4020000
Date Dimension has the dates included in the following format:
2015-01-01 00:00:00.000
Time Dimension is storing the time in the following format:
23:10:49 AM
Now, I have to make analysis using Tableau software, for which I need to join the two dimensions with the Fact table. I'm trying to create custom sql for creating a join, unfortunately I'm not able to do so.
Can anyone share how should I join the fact table with both the dimensions?
You are essentially looking for combining multiple tables using either Join Or Data Blending.
In tableau, you can combine data that exists across multiple tables or files by creating joins. Using joins to combine tables allows you to analyze data that have a relationship with each other.
Complete articles depicting all these steps can be found here
Connect to data and create your data source according to the examples
in Connecting to Data Sources.
After you select the file, database, or schema, double-click or drag a table to the join area of the data source page.
Double-click or drag another table to the join area. The join dialog box opens.
Add one or more join conditions by selecting a field from one of the available tables used in the data source, a join operator, and a field from the added table. Inspect the join condition to make sure it reflects how you want to connect the tables.
For example, in a data source that has a table of order information and another for users information, you could join the two tables based on the Region field that exists in both tables. Select the type of join.
When finished, click the "x" icon to close the Join dialog box.
In your case, You should go for these joins instead of Data blending. This is because, Data Blending does not create row level joins and is not a way to add new dimensions or rows to your data.
Data blending should be used when you have related data in
multiple data sources that you want to analyze together in a single
view. For example, you may have Sales data collected in an Oracle
database and Sales Goal data in an Excel spreadsheet. To compare
actual sales to target sales, you can blend the data based on common
dimensions to get access to the Sales Goal measure.
You can refer this article for more details
Related
I have an LDAP CSV file that is imported nightly and dumped into my MYSQL database. It has about 70000 employee records.
Included in that is empl#, email, group, supervisor, etc.
I have reports that are being generated from various web sites. We are dumping these reports in the database once a month. These reports usually have empl#, email, hits, logins, whatever...
My goal is to combine the report data and add in things like group, supervisor, etc based on empl#... Speed is a big concern because of the size of the database and number of users.
At first I thought of making a simple left join (given that report data is left - and that all people in the report may not be an employee). However the problem with that is that it does not take a snapshot in time. If report data from 6 months ago is viewed I don't want it mixed with current employee data - I want it to stay a snapshot in time.
What is the best way to handle this?
You will need a date column of some kind in both sets of data on which to join. Once you have that, you can simply put a condition that establishes the snapshot in the WHERE that limits the selection.
I have a series of tables in an Access 2007 database. I am trying to find a way of outputting a flat-file to an excel spreadsheet that combines all of the tables so that each row of the flatfile represents a unique combination of the table rows from each table.
For example, these tables:
Would combine to make this output table:
The challenges I'm facing are:
The 'input' tables can vary in number of rows and columns, as well as quantity
The total number of rows in the final output table can get quite large (200,000+ rows)
I know Excel and VBA (in Excel) well but almost nothing about Access
Is there a way to do this in Access? Is there some native functionality in Access that I'm completely overlooking? Any pointers (even if it's "you need to read into X and Y") would be greatly appreciated!
Thanks,
Adam
As noted above:
Create a new query. Select your 3 tables as the data sources. If desired, set up joins between tables by dragging a line between a field in one table to a field in another. Without joins you will get a Cartesian Product ... every from 1st table paired with every row of 2nd table, and then each of those combination paired with every row of 3rd table. Select the fields you want included in the result set. When the query returns what you need, save it and give it a name. Then you can export that named query to Excel.
If the table is large, you could hit Excel's row / column limit though.
I'm going to do my best to try to explain this. I currently have a data flow task that has an OLE DB Source transferring data from a table from a different database to a table to another database. It works fine but the issue I'm having is the fact that I keep adding duplicate data to the destination table.
So a CustomerID of '13029' with an amount of '$56.82' on Date '11/30/2012' is seen in that table multiple times. How do I make it so I can only have unique data transferring over to that destination table?
In the dataflow task, where you transfer the data, you can insert a Lookup transformation. In the lookup, you can specify a data source (table or query, what serves you best). When you chose the data source, you can go to the Columns view and create a mapping, where you connect the CustomerID, Date and Amount of both tables.
In the general view, you can configure, what happens with matched/non matched row. Simply take the not matched output and direct it to the DB destination.
You will need to identify what makes that data unique in the table. If it's a customer table, then it's probably the customerid of 13029. However if it's a customer order table, then maybe it's the combination of CustomerId and OrderDate (and maybe not, I have placed two unique orders on the same date). You will know the answer to that based on your table's design.
Armed with that knowledge, you will want to write a query to pull back the keys from the target table SELECT CO.CustomerId, CO.OrderId FROM dbo.CustomerOrder CO If you know the process only transfers data from the current year, add a filter to the above query to restrict the number of rows returned. The reason for this is memory conservation-you want SSIS to run fast, don't bring back extraneous columns or rows it will never need.
Inside your dataflow, add a Lookup Transformation with that query. You don't specify 2005, 2008 or 2012 as your SSIS version and they have different behaviours associated with the Lookup Transformation. Generally speaking, what you are looking to do is identify the unmatched rows. By definition, unmatched means they don't exist in the target database so those are the rows that are new. 2005 assumes every row is going to match or it errors. You will need to click the Configure Error Output... button and select "Redirect Rows". 2008+ has an option under "Specify how to handle rows with no matching entries" and there you'll want "Redirect rows to no match output."
Now take the No match output branch (2008+) or the error output branch (2005) and plumb that into your destination.
What this approach doesn't cover is detecting and handling when the source system reports $56.82 and the target system has $22.38 (updates). If you need to handle that, then you need to look at some change detection system. Look at Andy Leonard's Stairway to Integration Services series of articles to learn about options for detecting and handling changes.
Have you considered using the T-SQL MERGE statement? http://technet.microsoft.com/en-us/library/bb510625.aspx
It will compare both tables on defined fields, and take an action if matched or not.
Basics about the database
I am working on a (relatively) simple database that stores inventory data. I am using Microsoft Access 2010 in order to do this. I have six tables with the following relationships:
Relationships of Database
I have created forms which combine the Transaction table with Ordered, Received, Allocated, or Dispensed. Each form requests an amount which will then be used to update On Hand, On Order, or Allocated (from the Material table) respectively.
The Problem
For example, my form to update Transaction and Order should be able to take in the Amount ordered, save all the data from the fields to the Transaction and Order tables as well as add the amount from Amount to On Order in the Materials table.
I have been working on this database for the past two days. I have searched several times for possible ways to perform a similar function, but have come up with nothing. All the tutorials I have found which seem remotely close to what I need to accomplish are for versions of Access which are much older than 2010. Unfortunately I have had little experience with the actual coding within Access, so I am stuck clicking around within the buttons on its menus.
What I have tried
Currently, the program is set to run the following Update query:
Screenshot of update query
This query works if I have one Material stored in the database but adds all the Amount values from Ordered to On Order every time it is ran, which is unfortunately not what I need it to do. I only need each Amount value added to On Order once.
You need to relate the Ordered and Material tables by adding a foreign key field to the Material table, ex. OrderedFK (Long Integer). This new field must be updated whenever a row is inserted into the Ordered table (assuming the "No" Field is AutoNumber). This is typically performed by using a Form (Ordered) and Sub-Form (Material) and setting the sub-form' Link Master (No) and Link Child fields (OrderedFK).
You can then join the Ordered and Material tables on the Update Query to achieve the desired result.
I have an access form with a Record Source that pulls information from two tables
Select Rate.Prefix , Rate.Name, Provider.Carrier, Provider.Dest type,
from Rate
inner join Provider
on Rate.id = Provider.rateid
now when i a generate a datasheet form, with the above four columns. Prefix and Name will do filtering, but Carrier and Dest type will not do any filtering.
The project is an Access Project file(.adp), that links directly to sql database tables.
refer the images below
Filtering using the Name Column
After Filtering the data looks like in the screen below
Now the screen below shows trying to filter using Carrier Column (this is before Filtering)
Now after filtering, the data still remains the same as shown below
Anyone with ideas if datasheet do not support filtering, on joined table columns?