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Entity framework delete all entities extension method

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Unfortunately when deleting items in entity framework the SQL commands are issued as single DELETE statements for each entity. This really becomes a bottleneck when there are a several thousand items. This handy set of extension methods allows convenient and efficient deletion of all entities for a particular type T. The GetTableName<T> used function even takes into account table mappings set up with the ModelBuilder.

Thanks to Rul Jarimba on Stack Overflow for the GetTableName<T> function.

public static void DeleteAllEntities<T>(this DbContext db)
    where T : class
{
    var adapter = (IObjectContextAdapter)db;
    var objectContext = adapter.ObjectContext;
    var sql = string.Format("DELETE FROM {0}", objectContext.GetTableName<T>());
    var entityConnection = objectContext.ExecuteStoreCommand(sql);
}

public static string GetTableName<T>(this ObjectContext context)
    where T : class
{
    string sql = context.CreateObjectSet<T>().ToTraceString();
    Regex regex = new Regex("FROM (?<table>.*) AS");
    Match match = regex.Match(sql);

    string table = match.Groups["table"].Value;
    return table;
}

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