Dapper supports this directly. For example… string sql = “SELECT * FROM SomeTable WHERE id IN @ids” var results = conn.Query(sql, new { ids = new[] { 1, 2, 3, 4, 5 }}); unless you are using Postgres, in which case see this answer
I’ve written something like this before, but in the end didn’t get the chance to test it for performance. To insert data into two related table I’ve used a single stored procedure and some T-SQL tricks like table valued parameters, merge and output clause. Here is a sample script: First, create the sample tables: tblBase … Read more
This Git project is very helpful. I started from the same and did some changes as per my need. public sealed class DalSession : IDisposable { public DalSession() { _connection = new OleDbConnection(DalCommon.ConnectionString); _connection.Open(); _unitOfWork = new UnitOfWork(_connection); } IDbConnection _connection = null; UnitOfWork _unitOfWork = null; public UnitOfWork UnitOfWork { get { return _unitOfWork; … Read more
I just ran a test that works fine: var sql = “select cast(1 as decimal) ProductId, ‘a’ ProductName, ‘x’ AccountOpened, cast(1 as decimal) CustomerId, ‘name’ CustomerName”; var item = connection.Query<ProductItem, Customer, ProductItem>(sql, (p, c) => { p.Customer = c; return p; }, splitOn: “CustomerId”).First(); item.Customer.CustomerId.IsEqualTo(1); The splitOn param needs to be specified as the split … Read more
Dapper now supports custom column to property mappers. It does so through the ITypeMap interface. A CustomPropertyTypeMap class is provided by Dapper that can do most of this work. For example: Dapper.SqlMapper.SetTypeMap( typeof(TModel), new CustomPropertyTypeMap( typeof(TModel), (type, columnName) => type.GetProperties().FirstOrDefault(prop => prop.GetCustomAttributes(false) .OfType<ColumnAttribute>() .Any(attr => attr.Name == columnName)))); And the model: public class TModel { … Read more