DA0030: Gather tier interaction measurements for database projects
Applies to: 
Visual Studio 
Visual Studio for Mac
Note
This article applies to Visual Studio 2017. If you're looking for the latest Visual Studio documentation, see Visual Studio documentation. We recommend upgrading to the latest version of Visual Studio. Download it here
| Item | Value |
|---|---|
| Rule Id | DA0030 |
| Category | Profiling Tools Usage |
| Profiling method | Sampling |
| Message | Gathering interaction measurements for multi-tiered applications will help you understand database usage patterns and key data access delays. Try profiling the application again with the Tier Interaction Profiling option enabled. |
| Rule type | Information |
Cause
Calls to System.Data methods are a significant proportion of the profiling data and you have not collected tier interaction data in the profiling run. Consider profiling again and adding tier interaction data.
Rule description
This rule fires whenever there is significant activity in functions that reside in the System.Data namespaces, including System.Data.LinqSystem.Data.Linq.
Multi-tiered applications use layered services for their presentation and data layers. Often the data layer is a separate process running a database management system such as Microsoft SQL Server. The data layer might even be running on a separate machine from the rest of the application. Sampling profiles provide little insight into functions and services running out-of-process or remotely.
The profiling tools can gather timing information for multi-tiered applications that are interacting with a Microsoft SQL Server data layer using asynchronous calls to ADO.NET services. You must explicitly enable Tier Interaction Profiling. It is not turned on by default.
How to fix violations
This rule is for information only, and might not require corrective action.
For information about how to add tier interaction data to profiling data from the Visual Studio IDE, see Collect tier interaction data. For information about how to add tier interaction data from the command line, see Collect tier interaction data.