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copied!<p>I have a system that supports multiple products. Each product has its own database with the same exact schema.</p> <p>When I pass in the connection string as a parameter to my Data Context constructor it always uses the default database listed in the connection string, or the default database of the user connecting if I do not provide an Initial Catalog in the connection string.</p> <p>I would like to be able to have the system utilize a database without having to change the connection string and by passing in the database name as a parameter.</p> <p>Here is an example of the code I am using:</p> <pre><code>class Program { static void Main(string[] args) { var d = new Data("Data Source=(LOCAL);Initial Catalog=Database1;Integrated Security=true;"); var d1 = new Data("Data Source=(LOCAL);Initial Catalog=Database2;Integrated Security=true;"); Console.ReadLine(); } } internal class Data { public Data(string connection) { using (var ctx = new DataClassDataContext(connection)) { var query = from c in ctx.MyTable select c; try { Console.WriteLine(query.Count()); } catch (Exception ex) { Console.WriteLine(ex.Message); } } } } </code></pre> <p>If this code gets executed, then the first result will pull from Database1 and the second result will pull from Database2. I would like it to have the ability to pull from a database that is not provided in the connection string. The reason for this is because the database could change based on a specific scenario but the connection string will remain the same.</p> <p>Here is an example of what I am using to "fake" it, but I don't really think this is the best solution for this:</p> <pre><code>class oConnection { public string Server { get; set; } public string Database { get; set; } public bool IntegratedSecurity { get; set; } public string UserName { get; set; } public string Password { get; set; } } class Program { static void Main(string[] args) { var d = new Data(new oConnection { Database = "Database1", Server = "(Local)", IntegratedSecurity = true }); var d1 = new Data(new oConnection { Database = "Database2", Server = "(Local)", IntegratedSecurity = true }); Console.ReadLine(); } } internal class Data { private static string BuildConnection(oConnection connection) { var sb = new StringBuilder(); sb.Append("Data Source=" + connection.Server + ";Initial Catalog=" + connection.Database + ";"); if(connection.IntegratedSecurity) { sb.Append("Integrated Security=true;"); } else { sb.Append("user id=" + connection.UserName + ";password=" + connection.Password); } return sb.ToString(); } public Data(oConnection connection) { using (var ctx = new DataClassDataContext(BuildConnection(connection))) { var query = from c in ctx.MyTable select c; try { Console.WriteLine(query.Count()); } catch (Exception ex) { Console.WriteLine(ex.Message); } } } } </code></pre> <p>Another note: the goal of this is really to be able to support not having multiple different connection strings when running queries that will span across multiple databases. For example: If I want to query the account records from a database and then query some sort of lookup data from another database, I would have to create a new connection string for the context.</p> <p>Any help would be appreciated. Thanks</p>

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