While working on planning for a new application I decided to look at PostgreSQL vs. SQL Server Express. What drove my decision is the limitations on database size for SQL Server Express. I wanted to stick with Entity Framework as well and decided to go with PostgreSQL after looking at alternatives. I was very impressed with all the features of PostgreSQL and that the PostgreSQL team has a .NET Core Entity Framework provider.
Typically I create a sample console app when working with technology I have not used before (in this case PostgreSQL) so that I have a working example I can refer too and share. I posted a full working copy of this console app on my GitHub at this link.
The sample project (using .NET Core Entity Framework) will truncate a table in PostgreSQL then load a set of Cryptocurrency symbols and query that data with LINQ.
Sample Screen Shot:
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The project takes the approach of a typical setup of Dependency Injection of the service classes required to load and query the data.
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The GitHub project at this link has the steps on what is required to setup this code and run it.