How to connect to your data in Tableau
Right you have made the decision to utilise the benefits of data visualisation , to present your data in an easy to follow format.
Tableau is one of the top industry tools that allows you to manage your data, and present it in a fashion that enables decision making.
What are the ways to connect to your data in Tableau?
There are two possible ways to connect as follows:
(A) Accessing your data in a file
Below is a list of the possible file types. As can be seen Tableau accommodates not just files associated with their software, but also files commonly used by people and organisations in their day to day work.
The most common way to quickly access the files is through the menu on the side:
or through the file option at the top:
(B) Accessing a server by logging into it:
As can be seen above, the power of Tableau is that it enables the connection to a multitude of industry leading server technologies.
As long as you have the right credentials, and the server side security is setup correctly this should work seamlessly.
Connecting to a file
To start off one of the first things to check is your file format. We are going to import a XLSX workbook, with data on two tabs:
When Imported the screen will look like this:
On the left hand side the the sheets in table formats, in this example “data” and “lookup”, these are the two tabs in the source file:
All you need to do is drag one of them over to the right hand side upper panel. Tableau automatically will then load the data in , the bottom panel for you.
You should note that Tableau automatically assigns data types to each column.
Connecting to a server
As of the writing of this article, I have no server access, but below are a sample of some interfaces and data required for some of the server types:
(A) Cloudera Hadoop
(B) Google Cloud SQL
(C) Impala
(D) Microsoft SQL server
(E) Oracle
(F) Snowflake
(G) Teradata
What happens if I update my source data?
The great thing about Tableau is that , when you load in your data, you can save the project , and the connection to it within a file.
When you leave the connection to the source file is saved, and as long as the source file is not renamed or deleted, the data will always reload.
So in the raw file we have used in this example, record no 1 has a customer id of 2322.
Existing raw file in excel:
As I have the Table project open and the raw file connected, it will not allow me to change it.
Now I am going to change the customer id value to 2345 in the excel file, save and close.
When I reopen the Tableau project, as it has already saved the connection to the excel file, it reloads it, but with updated and refreshed data.
Now it can be seen that a refreshed copy of the data is in Tableau. This is very useful as all that needs to happen is a refresh of the data, and the user of the Tableau data visualisation has fresh information to work with.
Next step, interested to learn what are dimensions in Tableau?