Welcome to CA.Blocks.DataAccess Help Guide

This site is for developers who want to learn how to use the CA.Blocks.DataAccess micro ORM.

What is CA.Blocks.DataAccess

The CA.Blocks.DataAccess is a lightweight .NET library built on top of ADO.NET designed specifically for Onion and CQRS-type architectures working with relational databases. Its core functionality focuses on reducing the object-relational impedance mismatch that exists between the relational world and the object world of dotNET. Developers in the .NET world don't want to spend hours writing code to map results from ADO.NET data readers to objects in code or focusing on basic repeated connection details. CA.Blocks.DataAccess was written by Kevin Bosch and has been released as an open-source project under the MIT license.

Is CA.Blocks.DataAccess an ORM?

The short answer is no and it is not trying to be one. CA.Blocks.DataAccess falls into a family of tools known as micro-ORMs. These tools perform only a subset of the functionality of full-blown Object Relations Mappers, such as Entity Framework Core or NHibernate. Features vary by product. The following table provides a general idea of the capabilities that you can expect to find in a micro ORM compared to an ORM:

Function Micro ORM ORM
Map queries to objects
Connection Management Some
Caching results
Change tracking
SQL generation
Lazy loading
Unit of work support
Database migrations

The debate is never ending on the merits of an ORM. In general Micro ORMs usually perform faster than an ORM, and generally do not expect to know the schema of your database, whilst the projections are loosely coupled there is no direct coupling to the underlying tables.

To get the most out of any Micro ORM you will have to good Understanding of SQL, Row sets, and parameters. The CA.Blocks.DataAccess is no different. If you don’t want to work with SQL then this is not the library for you. The vast majority of performance problems with the CA.Blocks.DataAccess boils down to the underlying SQL, parameters or row sets transferred. The Blocks allow you to work directly with the SQL code whilst providing a good structure to reduce the impedance mismatch between the two technologies allowing a developer to move from the C# types into SQL parameters and then SQL into the C# types.

What does the CA.Blocks.DataAccess do

The blocks are built on ADO.NET, Whilst ADO.NET is a great technology, it is very low-level and verbose, it is dealing with connections, commands and readers. Whilst the drivers are very performant the verbose nature leads to a lot of boilerplate code.

If we consider the task of executing the result SQL server sp_who procedure into the following class:

    public class SpWhoResult
        public short spid { get; init; }
        public short ecid { get; init; }
        public string status { get; init; }
        public string loginame { get; init; }
        public string hostname { get; init; }
        public string blk { get; init; }
        public string? dbname { get; init; }
        public string cmd { get; init; }
        public int request_id { get; init; }

Here is the standard ADO.NET code for retrieving data from a database and materializing it as a list of SpWhoResult objects:

    public IList<SpWhoResult> ExecSpWhoUsingAdonet()
        var result = new List<SpWhoResult>();
        using (var connection = new SqlConnection("Server=(local);Database=tempdb;Integrated Security=SSPI;TrustServerCertificate=True"))
            using (var command = new SqlCommand("Exec sp_who", connection))
                using (var reader = command.ExecuteReader())
                    while (reader.Read())
                        var item = new SpWhoResult
                            spid = reader.GetInt16(reader.GetOrdinal("spid")),
                            ecid = reader.GetInt16(reader.GetOrdinal("ecid")),
                            status = reader.GetString(reader.GetOrdinal("status")),
                            loginame = reader.GetString(reader.GetOrdinal("loginame")),
                            hostname = reader.GetString(reader.GetOrdinal("hostname")),
                            blk = reader.GetString(reader.GetOrdinal("blk")),
                            // dealing with nulls
                            dbname = reader.IsDBNull(reader.GetOrdinal("dbname")) ? null : reader.GetString(reader.GetOrdinal("dbname")),
                            cmd = reader.GetString(reader.GetOrdinal("cmd")),
                            request_id = reader.GetInt32(reader.GetOrdinal("request_id"))
        return result;

Using the Blocks we can reduce the code above to the code below:

    public class YourDataAccessClass : SqlServerDataAccess
        public YourDataAccessClass() : base( new SimpleConnectionStringDataAccessConfig("Server=(local);Database=tempdb;Integrated Security=SSPI;TrustServerCertificate=True"))
        public IList<SpWhoResult> ExecSpWho()
            var cmd = CreateStoredProcedureCommand("sp_Who");
            return Execute(cmd).ToListOf<SpWhoResult>();

By design, the blocks wrap your data access methods into a class that is inherited from a base provider. The connection is set up in the constructor. The blocks will support inline use as above as well as dependency injection.

Once set up the typical data access method will involve

  1. Constructing a command from Sql Statement
  2. Executing that command to the native ADO.NET return type (scaler value, Row-set or output parameters)
  3. Mapping the ADO.NET result to the desired object result ie the O and M of ORM - Object Mapping.

The underlying connection is fully managed.


  1. The bulk of the conversion to and from ADO structures is abstracted using translators
  2. The translators are extendable so you can use custom converters if needed. The design allows for a flexible configuration, mingling core functions with your customizations. There are extension nuget packages that work with external types like NUlid, or JSON.
  3. Direct working with the SQL layer. If you like controlling exactly what the SQL does this is a good framework, as you are 100% in control of the SQL generated.
  4. Easy setup and Go with providers for SQL server, Sqlite, and MySQL.
  5. Is non-blocking and Works with multiple concurrent Async requests.


CA.Blocks.DataAccess has been released as open source by Kevin Bosch. Whilst it was only released on Nuget around 2016 Kevin has been using blocks since 2003, they are well-used and tested under different conditions. They have evolved as the .NET framework has evolved. Kevin tried using Entity framework and n-Hibernate but switched back to the Blocks as the defacto for the simple reason it was lightweight and far more predictable with far more control. In most cases, I was fighting with the ORM frameworks. The abstractions in a full-blown ORM result in tightly coupled code with the database, with average caching, opinionated implementation of the unit of work pattern, and some very odd SQL generation strategies, In addition security is very hard to control as the tool requrest full read and write access vertically, and horizontally.

I found that whilst the Entity framework and n-Hibernate excel at CRUD-type applications ( where mostly 1-1 mappings are required) and no security constraints. I was doing a lot of workarounds and conversions trying to use them in either CQRS, layered onion or repository type Architectures. I have seen many code bases use Entity framework for data access in a Repository Pattern, and in most cases, you end up writing more code in the object world to avoid working to a few SQL statements. A tell-tale sign is you using reflection or mapping to copy objects of similar structures across boundaries. In these designs, You simply replace one impedance mismatch with another.