How to install support for UML diagrams in Visual studio 2019?

Question

visual studio

Visual Studio 2019 Professional 16.6.3
Can't find Modeling Projects (diagramming tool) in project templates.
What do I need to install or change to get this tool?

Need this

Answer 1

Perhaps it is "Architectural Layer Diagrams", then it is only available in the "Enterprise" version.
https://visualstudio.microsoft.com/vs/compare/

Answer 2

The error message and the given listing do not correspond to each other,
something you mixed up when publishing,
but in this piece - the quote mark is not closed - it should be like this:

or die("Не удается записать запрос в базу данных!");