Creating dataflows using linked and computed entities

hey this is Matthew from bi-polar in this video we're going to look at the second way that power bi lets us create new data flows specifically we're going to look at using linked entities from other data flows that have already been created let's check it out in this video we're continuing to look at some of the basics of power bi data flows in the last video we looked at how to create a new data flow by defining the entities ourselves connecting to external data sources using power query online in this video we'll look at how we connect to existing data flows to make them available inside our data flow in the same workspace or a different one let's check it out so here we are in my bi polar workspace I'm going to start by creating a new data flow and here I'm going to choose the second option that's available I'm going to link entities from other existing data flows now when I come in here I will first of all be prompted to connect to the power bi service assuming that I'm already signed in which I should be using my edger active directory organizational account I can simply choose next on the next screen I'll see a list of all of the workspaces that are using the new or v2 workspace experience that contain data flows and where I'm a member which will give me the ability to access and connect to those data flows for this demo I want to start off with the data flow that I've created in the previous demo so I will expand out my bi polar blog I will come down to this creating data flows one of four data flow that I created the last time and I will connect to this customer data flow but I also want to enrich this data flow with data from an entities that are in other workspaces and in the data flows that are inside them so here I can come over to my adventureworks workspace connects to the adventureworks data flow that's inside it and I can pull in customer address and address and product any other data flow or any other entity that I choose and when I have selected all of the entities from all of the data flows in all of the workspaces that I want I can then choose to transform data and here I will see all of the entities that I've defined and you'll notice that there is a message that's being displayed saying that these are linked entities that can't be modified here they can only be edited in this source data flow this is really a key concept a linked entity is essentially a pointer to the data where it already exists creating a linked entity and even refreshing this data flow will not cause that data to be copied but I can't use it as the building block for additional entities that exist inside this workspace so here I will say that I want to combine tables so if I say combine merge queries as new I can choose the customer entity on the left I can choose the customer address entity on the right and I can choose the customer ID column in both of these entities to merge them on so when I'm done and I choose ok similar to what we saw in the last demo I'm getting a warning about these entities or this new entity containing a column with a complex type so when I scroll all the way to the right I can then expand out customer address set a couple things here and choose ok to resolve that warning so here I now have a single entity that I've defined using two other linked entities as sources and now I can give it a name and when I choose save and close' and when I choose save them close I can name the data flow and again choose to refresh it but as you can see from this screen the only entity that is physically stored in this data flow or in the CDM folder that is created in Azure for this data flow is that new customers with addresses data flow the linked entities their data remains in these source data flow and their source CDM folders so we don't duplicate we don't have redundant data and when we refresh this data flow the only query that is actually being run is the query for this customers with addresses entity that we've defined in this video we've looked at the second of four ways that we can define new data flows inside our power bi workspaces we've got two more videos coming up I hope you'll come back you

Channel: BI Polar

Views: 2,457

Rating: 4.9298244 out of 5

Keywords: Power BI, dataflows, Power BItes, linked entities, computed entities, tutorial, Power Query

Id: 0Z_5k-ZzEM8

Length: 5min 42sec (342 seconds)

Published: Mon Nov 04 2019