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?

Tableau Desktop versus Tableau Server

Estimated reading time: 5 minutes

Are you working on a data analytics project, and seeking a way to present your data visually?

Data Visualisation achieves this, and there are many products on the market place that you could use.

In this blog post, we are going to discuss Tableau , one of the leading data visualisation tools in the market place.

So before we dive into this tool and start looking at it, we need to ask the question, why pursue data visualisation?

In the pursuit of a better understanding of data a company holds, a data analyst will need access to multiple tables and records.

They first of all will need to get the right data, usually through SQL select statements.

The challenge then is how do they take all this data and present it in a meaningful way? Data visualisation looks to fix this problem by:

  • Aggregating data into meaningful groups.
  • Removing the need to trawl through rows and rows of data.
  • Allow the ability to drill down deeper, to see what makes up a set of data.
  • Create visually appealing pages, that quickly give the viewer an understanding of what is going on with the data, and spot visual patterns.

So what is Tableau Desktop?

Tableau Desktop is used by end users with the following functionality in mind:

  • Interactive dashboards
  • The ability to connect to data on-premises or in the cloud.
  • Exceptional analytics demand more than a pretty dashboard.
  • Quickly build powerful functionality:
    • That allows calculations from existing data.
    • Enables drag and drop of data.
    • Provides statistical output.
  • Make your point with trend analyses, regressions and correlations for tried-and-true statistical understanding.
  • It also allows you to:
    • Ask new questions, look at the data from a way you had not thought of before.
    • Spot trends – See visually how data is moving in a direction, can you benefit from this insight?
    • Identify opportunities and make data-driven decisions with confidence.

As a result you can share/visualise the underlying data securely using Tableau Server.

So what is Tableau Server?

Tableau Server on the other hand is used as follows:

  • It is an enterprise solution, you can let the whole organisation leverage the power of its functionality.
  • In light of this, it empowers your business with the freedom to explore data in a trusted environment, and it doesn’t limit them to pre-defined questions, wizards or chart types.
  • For the purpose of understanding your data better, it has the functionally for you to ask questions, and these use sophisticated algorithms.
  • Also, it has artificial intelligence capabilities that allow the software to find insights you may not have been aware of.

You can also harvest the following capabilities:

  • Connect to Cloudera Hadoop, Oracle, AWS Redshift, cubes, Teradata, Microsoft SQL Server, for your enterprise needs.
  • Similarly, it has Governance capabilities so that you can centrally manage all of your metadata and security rules.
  • The Tableau platform is easy to deploy, scale and monitor.

If security is something that is important:

  • Whether you use Active Directory, Kerberos, OAuth or another standard, Tableau seamlessly integrates with your existing security protocols.
  • Easily track and manage content, users, licences and performance.
  • Quickly manage permissions for data sources and content and monitor usage visually.
    • Tableau Data Management helps you better manage the data within your analytics environment, ensuring that trusted and up-to-date data is always used to drive decisions.

So you have seen both, what areas should you look at before deciding on which to use?

CriteriaTableau ServerTableau Desktop
LicensingCentrally managed, licenses can be easily redistributed if a person leaves the organisation.Managed on a case by case basis, if a person leaves the license needs to be transferred, can cause additional administration.
SecurityPermissions are managed centrally, on access and ability to update the dashboard. It can leverage the power of Active Directory, Kerberos, OAuth.Permissions managed locally, based on the corporate network setup, which is usually a username and password.
ConnectivityWorks well with popular enterprise data sources like Cloudera Hadoop, Oracle, AWS Redshift, cubes, Teradata, Microsoft SQL Server.You can connect to data on-premises or in the cloud – whether it’s big data, a SQL database, a spreadsheet or cloud apps like Google Analytics and Salesforce.
Artificial IntelligenceAs this is usually installed on the corporate network the ability to perform complex calculations has more power on dedicated servers.No capability on the desktop version
ScalabilityHighly scalable allows for more users and data to be added, becomes easier to manage.As stored locally, you are subject to the capabilities and size of the computer you are on. The larger the volumes, the longer the processing takes, and you could run out of space locally.
DevelopmentIt would depend on the user’s rights, not might be possible/ideal if the server is just used for hosting and managing the dashboards.It can be achieved with the desktop but then sharing it has its limitations per Sharing below. On the other hand, when development is complete it could be loaded to the server for sharing with other users.
Data ManagementYou can manage all your data centrally, thus if you have multiple dashboards, they will work off the one set of data ensuring consistency.If you have a number of people developing dashboards that are similar, they need to ensure where they pull their data from is consistent, so that the outputs do not give conflicting messages.
Enterprise CapabilityHas the ability to manage a large corporate network of users.None available used more for local development.
SharingAs long as the user can log in to the server
they can see dashboards they have access to.
Can be shared locally, the recipient must have Tableau installed
to see the visualisation.
EditingThe dashboard can only be edited on the server, with appropriate permissions.Local versions could be edited by users, thus you could end
up with multiple versions of the same dashboard.

So in summary:

In order to make a decision on which route to take, the following questions should be asked:

  • What is the size of your organisation?
  • Does your workforce need development capabilities?
  • How important is it to be able to manage your data? Does it need to be controlled centrally?
  • Can you benefit from scaling for:
    • Licensing costs.
    • Data management.
    • User management.
    • Dashboard distribution.
    • Scalability – Will your existing data be extensive and grow over time?

As a result a lot of the decision will come down to cost, the size of your data , distribution of dashboards and the no of users.