StoredProcedureEFCore 0.3.8

Execute stored procedures with Entity Framework Core

DbContext extension with LoadStoredProc method which creates an IStoredProcBuilder to build a stored procedure with a custom mapping strategy using the provided DbDataReader extension.

The method handles :

• Extra column in result set
• Extra property in model
• Null values in result set
• Underscores in result set column names ("column_name" is mapped to ColumnName property)
• Int (db) to enumeration (result model) mapping

Entity Framework Core supports stored procedure since 2.1

This library will soon be obsolete, but it has few advantages compared to FromSql:

• Extra property in the model won't throw an exception. The property keeps its default value
• The interface is easier to use (I think). Output parameters and return values seem difficult to use with EFCore
• It is 30% faster

Example

List<Model> rows = null;

ctx.LoadStoredProc("dbo.ListAll")
   .AddParam("limit", 300L)
   .AddParam("limitOut", out IOutParam<long> limitOut)
   .Exec(r => rows = r.ToList<Model>());

long limitOutValue = limitOut.Value;

ctx.LoadStoredProc("dbo.ReturnBoolean")
   .AddParam("boolean_to_return", true)
   .ReturnValue(out IOutParam<bool> retParam)
   .ExecNonQuery();

bool b = retParam.Value;

ctx.LoadStoredProc("dbo.ListAll")
   .AddParam("limit", 1L)
   .ExecScalar(out long l);

API

DbContext

IStoredProcBuilder             LoadStoredProc(string name)

DbDataReader

List<T>                              ToList<T>()
Dictionary<TKey, TValue>             ToDictionary<TKey, TValue>(Func<TValue, TKey> keyProjection)
Dictionary<TKey, List<TValue>>       ToLookup<TKey, TValue>(Func<TValue, TKey> keyProjection)
HashSet<T>                           ToSet<T>()
List<T>                              Column<T>()
List<T>                              Column<T>(string columnName)
T                                    First<T>()
T                                    FirstOrDefault<T>()
T                                    Single<T>()
T                                    SingleOrDefault<T>()

All these methods have a corresponding async method : ToListAsync, ToDictionaryAsync, ...

IStoredProcBuilder

IStoredProcBuilder                   AddParam<T>(string name, T val)                             // Input parameter
IStoredProcBuilder                   AddParam<T>(string name, T val, out IOutParam<T> outParam)  // Input/Ouput parameter
IStoredProcBuilder                   AddParam<T>(string name, out IOutParam<T> outParam)         // Ouput parameter
IStoredProcBuilder                   ReturnValue<T>(out IOutParam<T> retParam)
void                                 Exec(Action<DbDataReader> action)
void                                 ExecNonQuery()
void                                 ExecScalar<T>(out T val)

Exec, ExecNonQuery, and ExecScalar have a corresponding async method.

Installation

Install-Package StoredProcedureEFCore

Why ?

Stored procedure execution was not supported in entity framework core:

• Raw store access APIs: Support for ad hoc mapping of arbitrary types #1862
• Stored procedure mapping support #245