Category Archives: Database

IQueryable vs IEnumerable vs IHaveHeadache

Yes.. this ist just another blog post about IEnumerable and IQueryable. But the topic is quite important and I think it worth discussing about both approaches. Recently I had a discussion with a software architect about the implementation of the repository pattern. The question was: Should the repository return IEnumerable or IQueryable? So let’s do… Read More »

Entity Framework and Expression Queries

In my current project I had to generate a Entity Framework query based on some search criterias defined in a dictionary. The structure of the dictionary was similar to this example here: var searchCriteria = new Dictionary<string, List<string>>() { { "FirstName", new List<string> { "Darko", "NoName" } }, { "LastName", new List<string> { "Micic", "Müller",… Read More »

Using Neo4j Graph DB With C#.NET

In the following example I’ll explain how to access the Neo4j database with the Neo4jClient. I’ve used both components in a project and was very satisfied. Information about Neo4j: http://neo4j.org/ Information about Neo4jClient: http://hg.readify.net/neo4jclient/wiki/Home For this demo I created an entity class called Person. This class will be represented in Neo4j as a node. public… Read More »

Entity Framework ‘Code First’ Approach and Domain-Driven Design

With the Code First approach we can create clean entities without any EF specific code. After the first demo, I saw that you have to deal with the IDbSet interface, which is placed in the Entity Framework library. When you place the entities in your business dll you have to reference the EF library. This… Read More »

Using A Document Database – RavenDB

RavenDB is a document database. The main difference between RavenDB and a relational database is, that RavenDB doesn’t support relation between the rows/entities/documents. A document contains structural data, which is stored in JSON format. This is a quickstart into RavenDB: Step 1 – Database: Create a new database. This DB doesn’t contain any structure. It’s… Read More »