And, YES, it's tempting to keep the string specially since:
0. MySQL seems to return things/integrals in string
1. MySQLNet converts byte array to string anyway (GC for that string won't really happen immediately)
2. there would be users (like me) who'd call GetString() instead of the more appropriate GetInt32, for example. If they can get away with that in ODBC.NET/SqlClient, they'd expect the same behavior in MySQLNet.
I agree with Reggie on structs for different MySQL types, though we'd have to keep an internal "DB Null" flag since structs can't be null when unboxed.
Marlon
From: "Reggie Burnett" <[EMAIL PROTECTED]>
To: "'Daniel Morgan'" <[EMAIL PROTECTED]>,"'Marlon Baculio'" <[EMAIL PROTECTED]>
CC: "'Mono-List'" <[EMAIL PROTECTED]>
Subject: RE: [Mono] MySQL Managed Provider
Date: Wed, 22 Jan 2003 23:32:44 -0600
Using a set of structs for MySQL types is the right approach.
I'll probably knock this out pretty quick so if anyone has any code for
this, send it now.
Reggie
> -----Original Message-----
> From: Daniel Morgan [mailto:[EMAIL PROTECTED]]
> Sent: Wednesday, January 22, 2003 11:17 PM
> To: Marlon Baculio
> Cc: Mono-List; [EMAIL PROTECTED]
> Subject: RE: [Mono] MySQL Managed Provider
>
> I would follow the model like System.Data.SqlTypes is for Microsoft
SQL
> Server types. Except, have a namespace Mono.Data.MySqlTypes which
holds
> types like the ones that MySQL has, such as, MySqlInt for int, and
> MySqlDateTime for datetime.
>
> As far as Type coersion, the ODBC.net provider probably keeps the data
as
> a
> string until you try to use it, such as, GetString or GetInt32 or
> GetInt16.
>
> Have you tried using something like the ProviderFactory found in
> Mono.Data?
>
> Here is some sample code:
>
> // test.cs
> using System;
> using System.Data;
>
> public class Test {
> public static void Main(string[] args) {
> IDbConnection conn =
> ProviderFactory.CreateConnectionFromConfig("PubsConnStr");
> Console.WriteLine("Open Connection");
> conn.Open();
> IDbCommand cmd = conn.CreateCommand();
> cmd.CommandText = "select somecolumn from sometable";
> IDataReader reader = cmd.ExecuteReader();
> reader.Read();
> Console.WriteLine("SomeColumn: " +
reader["somecolumn"].ToString());
> }
> }
>
> Or you could use:
> IDbConneciton conn =
> ProviderFactory.Provider["Mono.Data.MySql"].CreateConnection();
> conn.ConnectionString = "Server=localhost;Database=test;User
> ID=mysql;Password=mysecret";
> conn.Open();
>
> I have provided a modified test.exe.config for you.
>
> <?xml version="1.0" encoding="utf-8" ?>
> <configuration>
> <configSections>
> <sectionGroup name="mono.data">
> <section name="providers"
> type="Mono.Data.ProviderSectionHandler,Mono.Data" />
> </sectionGroup>
> </configSections>
> <appSettings>
> <add key="MySqlOdbc"
>
value="factory=System.Data.Odbc;DSN=myodbcdsn;UID=someuser;PWD=somepass"
> />
> <add key="MonoMySql"
> value="factory=Mono.Data.MySql;Server=localhost;Database=test;User
> ID=mysql;Password=myscret" />
> <add key="MySqlNet"
>
value="factory=ByteFX.Data.MySQLClient;Server=localhost;Database=test;Us
er
> ID=mysql;Password=myscret" />
> </appSettings>
> <mono.data>
> <providers>
> <provider
> name="System.Data.Odbc"
>
connection="System.Data.Odbc.OdbcConnection"
>
adapter="System.Data.Odbc.OdbcDataAdapter"
> command="System.Data.Odbc.OdbcCommand"
> assembly="odbc"
> description="ODBC (Mono)" />
> <provider name="Mono.Data.MySql"
>
connection="Mono.Data.MySql.MySqlConnection"
>
adapter="Mono.Data.MySql.MySqlDataAdapter"
> command="Mono.Data.MySql.MySqlCommand"
> assembly="Mono.Data.MySql"
> description="MySQL (Mono)" />
> <provider name="ByteFX.Data.MySQLClient"
>
> connection="ByteFX.Data.MySQLClient.MySQLConnection"
>
adapter="ByteFX.Data.MySQLClient.MySQLDataAdapter"
>
command="ByteFX.Data.MySQLClient.MySQLCommand"
> assembly="ByteFX.Data"
> description="MySQL (ByteFX)" />
> </providers>
> </mono.data>
> </configuration>
>
> -----Original Message-----
> From: Marlon Baculio [mailto:[EMAIL PROTECTED]]
> Sent: Wednesday, January 22, 2003 11:25 PM
> To: [EMAIL PROTECTED]
> Cc: [EMAIL PROTECTED]
> Subject: RE: [Mono] MySQL Managed Provider
>
>
> Hi Daniel,
>
> All my code in the data layer is using the generic interfaces (such as
> IDataReader) as opposed to provider-specific classes (except when
> instantiating a concrete provider class, in which case, what I do is
> create
> an alias using the "using" C# keyword, so that my code just refers to
the
> (abstracted) alias then I just switch back-and-forth between ODBC.NET
and
> MySQLNet by changing the alias).
>
> Since my code has been coded around ODBC.NET, the problems I find are
> compatibility issues, for example:
>
> 0. [enhancement] In connection string, support for "UID" in addition
to
> "user id"
>
> 1. [bugs] parsing value for MySQLFieldType.BYTE should use
Byte.Parse()
> and
> not Int16.Parse()
>
> 2. ODBC.NET is more forgiving for type coercion. For example, you can
call
> IDataReader.GetString() against an integral type, or you can call
> IDataReader.GetInt32() against a 16-bit column.
>
> 3. I'm also worried about how MySQLField is storing field values as
> objects.
> This will require a lot of boxing and unboxing when value is passed to
the
> client-code, specially if we want to support more relaxed type
coercion
> (although the cost of the boxing/unboxing would be negligible compared
to
> the overall SQL call, but I'm a performance freak so I tend to be
paranoid
> :). My recommendation is to create an abstract class for a field
value,
> then
> derive classes for each type, for example:
>
> abstract class MySQLFieldValue
> {
> ...
> public virtual byte GetByte();
> public virtual Int32 GetInt32();
> ...
> };
>
> class MySQLByteFieldValue : MySQLFieldValue
> {
> public MySQLByteFieldValue(byte[] data)
> {
> ...
> }
> public override byte GetByte()
> {
> return _value;
> }
> public override Int32 GetInt32()
> {
> // no boxing required, while being type-relaxed
> return /*(Int32)*/ _value;
> }
>
> private byte _value;
> };
>
> 4. I feel confident on using MySQLNet because of its performance and
the
> fact that I can fix the code myself being open source. It would be
nice
> though to support connection pooling. Maybe we can create a simple
> ObjectPool that we can use in MySQLConnection.Open() and .Close().
>
>
> (I hope Reggie is reading this) I think what I'm going to do is
continue
> making the changes on my copy of the MySQLNet code and then send the
> original and modified code to Reggie so he can do a diff and decide if
my
> changes deserve to be included.
>
> I've been frequenting the "MySQL forum section" at
> http://www.asp.net/Forums/ShowForum.aspx?tabindex=1&ForumID=56
> Maybe we can get some help/idea from there.
>
> Thank you so much Daniel! I'm been following Mono for quite sometime
now,
> hoping that eventually I will use that to run my ASP.NET web site on
> Linux.
>
>
> Marlon Baculio
> [EMAIL PROTECTED]
>
>
> >From: "Daniel Morgan" <[EMAIL PROTECTED]>
> >To: "Marlon Baculio" <[EMAIL PROTECTED]>
> >CC: "Reggie Burnett" <[EMAIL PROTECTED]>
> >Subject: RE: [Mono] MySQL Managed Provider
> >Date: Wed, 22 Jan 2003 21:57:22 -0500
> >
> >Hi Marlon,
> >
> >Reggie Burneet is the lead developer of MySQLNet. He would be glad
to
> have
> >patches to the provider. Can you be more specific about the problems
you
> >are having. Can you provide simple test cases?
> >
> >Same thing with the provider in Mono - patches are welcome.
> >
> >Mono.Data.MySql is in maintenance mode and is mainly meant to work on
> Mono.
> >Try using MySQLNet which will become the choice for Mono in the
future
> >since
> >it works on Mono and .NET, faster,
> >and no dependencies on a client library.
> >
> >Have you been using the various interfaces in ADO.NET, such as,
> >IDbConnection, IDbCommand, IDataReader, IDbDataAdapter, etc. ?
> >
> >IDbConnection dbcon = new MySqlConnection();
> >dbcon.ConnectionString = "Server=localhost;Database=test;User
> >ID=mysql;Password=mysecret";
> >IDbCommand dbcmd = dbcon.CreateCommand();
> >dbcmd.CommandText = "select * from sometable";
> >IDataReader reader = dbcmd.ExecuteReader();
> >
> >These interfaces provide a generic way to use different providers.
Also,
> >there is the ProviderFactory and DataTools found in Mono.Data.dll
which
> can
> >be used to dynamically create connections, commands, parameters, and
> >adapters via some configuration.
> >Take a look at the test for it at mcs/class/Mono.Data/Test/test.cs
> >which uses a .config file named test.exe.config
> >for various app settings and providers.
> >
> >Daniel
> >
> >-----Original Message-----
> >From: Marlon Baculio [mailto:[EMAIL PROTECTED]]
> >Sent: Wednesday, January 22, 2003 1:09 AM
> >To: [EMAIL PROTECTED]
> >Subject: [Mono] MySQL Managed Provider
> >
> >
> >Hi Daniel,
> >
> >(Please excuse me if this e-mail or this address is inappropriate.)
> >
> >I've been checking out MySQLNet from ByteFX. I've heard you are also
> >writing
> >a separate MySQL Managed Provider for Mono.
> >
> >I'm writing a web site that uses MySQL using ODBC.NET. I am not
satisfied
> >with the performance so I am looking for alternatives. MySQLNet from
> ByteFX
> >looks so promising but there's a few problems with it. My ultimate
test
> for
> >ADO.NET compatibility (at least for my site) is to able to switch
between
> >ODBC.NET and MySQLNet (or any MySQL Provider) without a problem like
> this:
> >
> >using DBConnection = Microsoft.Data.Odbc.OdbcConnection;
> >using DBCommand = Microsoft.Data.Odbc.OdbcCommand;
> >
> >//using DBConnection = ByteFX.Data.MySQLClient.MySQLConnection;
> >//using DBCommand = ByteFX.Data.MySQLClient.MySQLCommand;
> >
> >
> >In fact, I've been making bug fixes/adjustments to my copy of the
ByteFX
> >code until I get a word from Reggie Burnette.
> >
> >If I don't get a response from him, I wish to ask you the following
> >question:
> >
> >0. Any timeline or chance your provider will use pure C# to talk
directly
> >with the MySQL Server?
> >1. Any immediate plans for connection pooling?
> >2. Any chance I could contribute? (example: for ByteFX, I wish to
make it
> >more forgiving on type coercions like ODBC.NET, and less
boxing/unboxing)
> >
> >So, basically, I'm torn as to which project I would use in my site
:-)
> >
> >Thank you!!!
> >
> >Marlon Baculio
> >[EMAIL PROTECTED]
> >
> >
> >
> >_________________________________________________________________
> >Add photos to your e-mail with MSN 8. Get 2 months FREE*.
> >http://join.msn.com/?page=features/featuredemail
>
>
> _________________________________________________________________
> Protect your PC - get McAfee.com VirusScan Online
> http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963
_________________________________________________________________
The new MSN 8: smart spam protection and 2 months FREE* http://join.msn.com/?page=features/junkmail
_______________________________________________
Mono-list maillist - [EMAIL PROTECTED]
http://lists.ximian.com/mailman/listinfo/mono-list
