Prepare the data · Topic 1 of 8
Connecting to Data and Data Source Settings
PL-300 connecting to data: choosing connectors, using a shared semantic model, editing credentials in data source settings and setting privacy levels.
- 5 min
- A shared semantic model is reached by a live connection and needs Build permission.
- You can add report level measures to a live connection, and you can build a composite model on top of it.
- Data source settings hold credentials and privacy levels. Global permissions apply to every file on your computer.
What it is
Power BI Desktop connects to hundreds of sources through connectors: files, databases, online services and web endpoints. You can also connect to a shared semantic model that someone else already built and published, which lets many reports reuse one set of tables, relationships and measures. Once connected, data source settings control how Power BI signs in and how it lets data from different sources mix.
How it works
Connecting to sources
Select Get data and choose a connector. The common groups are below.
| Group | Examples | Notes |
|---|---|---|
| Files | Excel, CSV, JSON, XML, PDF, a whole folder | A folder connector combines many files with the same layout |
| Databases | SQL Server, Azure SQL Database, Oracle | Many support both Import and DirectQuery |
| Online services | SharePoint Online list, Dataverse, dataflows | Sign in with an organizational account |
| Other | Web, OData feed, Blank query | Web reads a URL, and a Blank query lets you write M by hand |
The Navigator window lets you preview and tick tables or sheets. Choose Load to import as is, or Transform Data to open the Power Query Editor first. As a rule, transform before loading, so that bad data never reaches the model.
Connecting to a shared semantic model
Use Get data and then the OneLake catalog (the Data hub) to find semantic models in the Power BI service. When you pick one, you create a live connection: the report holds no data, and every query goes to the shared model.
- You need Build permission on the semantic model to create new reports on it.
- You cannot change the shared model's tables from the report, but you can add report level measures.
- To extend the model with your own tables, choose to make changes to this model. This builds a composite model, where your local tables sit beside the shared one.
The benefit is a single source of truth. If the owner fixes a measure, every report built on the model gets the fix.
Data source settings
Open Transform data and then Data source settings. There are two views.
- Data sources in current file shows the sources this report uses.
- Global permissions shows credentials saved on your computer for every report.
Select a source and choose Edit Permissions to change the credentials (Windows, Basic, organizational account, Web API or Anonymous) and the privacy level. Clear Permissions removes saved credentials, so the next refresh asks again. Change Source edits the path or server name, which is how you repoint a report from a test database to a production one.
In the Power BI service, credentials for a published model are edited in the semantic model settings under Data source credentials. If a scheduled refresh fails because a password changed, that is where you fix it.
Privacy levels
Privacy levels stop data leaking between sources when Power Query combines them, for example when it sends a value from one source into a query against another.
| Level | Meaning |
|---|---|
| Private | Sensitive data. It is never shared with another source. |
| Organizational | Visible to a trusted group in the organization. It can be shared with other organizational sources. |
| Public | Open data. It can be shared with any source. |
When you merge a Private source with another source, Power Query isolates them and may show the error "Information is being sent to another source". Fix it by setting correct privacy levels, not by ignoring the problem. The Ignore the Privacy Levels option exists in the current file settings but removes the protection.
A worked scenario
An analyst loads sales from an Azure SQL Database and a budget file from SharePoint, then merges them. Refresh fails with a privacy error. She opens Data source settings, sets the SQL source to Organizational and the SharePoint source to Organizational, and the merge works. Later the database moves to a new server, so she uses Change Source instead of rebuilding the query. In the service, the data owner updates Data source credentials after a password rotation.
What to remember for the exam
- A shared semantic model is reached by a live connection and needs Build permission.
- You can add report level measures to a live connection, and you can build a composite model on top of it.
- Data source settings hold credentials and privacy levels. Global permissions apply to every file on your computer.
- The three privacy levels are Private, Organizational and Public.
- Change Source repoints a query to a different server or file without rebuilding it.
To change the server name for every query that uses it, use a Power Query parameter instead of editing each query. Parameters are on the next page.
How the exam asks about this
- "Many reports must share one set of measures." Connect to a shared semantic model.
- "You get an error combining two sources." Check the privacy levels.
- "The refresh now fails after a password change." Update credentials in the service.
- "Users cannot create a report on a semantic model." They lack Build permission.
Common mistakes
Choosing Load too early. Transform first, so errors never reach the model.
Ignoring privacy levels. Setting Ignore hides the warning but also removes the protection.
Importing a model you could reuse. If a certified semantic model already has the tables, connect to it.
Editing credentials in Desktop only. The published model has its own credentials in the service.
Check yourself
What permission do you need to create a report from a shared semantic model?
Build permission on the semantic model.
Which privacy level keeps a source from being shared with other sources?
Private.
Where do you change the server name a query uses?
Data source settings, with Change Source.
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