Synopse Open Source

On the mORMot roadmap, we added a new upcoming feature, to implement one-way callbacks from the server.
That is, add transparent "push" mode to our Service Oriented Architecture framework.

Aim is to implement notification events triggered from the server side, very easily from Delphi code, even over a single HTTP connection - for instance, WCF does not allow this: it will need a dual binding, so will need to open a firewall port and such.

It will be the ground of an Event Collaboration stack included within mORMot, in a KISS way.
Event Collaboration is really a very interesting pattern, and even if not all your application domain should be written using it, some part may definitively benefit from it.
The publish / subscribe pattern provides greater network scalability and a more dynamic SOA implementation: for instance, you can add listeners to your main system events (even third-party developed), without touching your main server.
Or it could be the root of the Event Sourcing part of your business domain: since callbacks can also be executed on the server side (without communication), they can be used to easily add nice features like: complete rebuild, data consolidation (and CQRS), temporal query, event replay, logging, audit, backup, replication.

I like very much user participation (SCRUM / Agile is my moto) - I never believe to be always right nor write perfect code, and I'm convinced Open Source projects are also about sharing ideas among people of good will.

So when an active member of the forum reported his confusion / concern about some of the ORM methods of our framework, it appeared that some re-factoring was necessary.

There was a breaking change about the TSQLRecord.Create / FillPrepare / CreateAndFillPrepare and TSQLRest.OneFieldValue / MultiFieldValues methods: for historical reasons, they expected parameters to be marked as % in the SQL WHERE clause, and inlined via :(...):.
Since revision 1.17 of the framework, those methods expect parameters marked as ? and with no :(...):.

For instance, instead of writing:

 aRec.CreateAndFillPrepare(Client,'Datum=?',[],[DateToSQL(EncodeDate(2012,5,4))]);

 aRec.CreateAndFillPrepare(Client,'Datum=?',[DateToSQL(EncodeDate(2012,5,4))]);

The void [], array (used for replacing % characters) is not to be written any more, since the default is to use bound parameters via ? and not textual replacement via %.

Due to this breaking change, user code review is necessary if you want to upgrade the engine from 1.16 or previous.

In all cases, using ? is less confusing for new users, and more close to the usual way of preparing database queries - e.g. as used in SynDB.pas units.

Both TSQLRestClient.EngineExecuteFmt / ListFmt methods are not affected by this change, since they are just wrappers to the FormatUTF8() function.

Here is some unbelievable news retrieved from "Te Waka o Delphi" blog:

From XE3 onwards, your Delphi Professional EULA will prohibit you from using Delphi Professional for anything other than local data access.
If you want to build client/server database applications using Delphi Professional, you will be required to purchase a “Client/Server Add-On” pack.

This goes beyond the fact that you do not get (or can otherwise use or install) client/server drivers for the DBExpress or other “built in” data access frameworks, but extends even to 3rd party data access technologies.
That is, whatever you may be able to do or achieve – technically – using some 3rd party component or library with you Delphi Professional compiler, you cannot legally create a client/server application.
Never mind any 3rd party components or libraries, this same prohibition will apply even if you are using naked, unadorned Microsoft ADO.

Damn show-stopper for me.
Embarcadero is killing Delphi.

Our very own mORMot Open-Source framework is fully Client-Server oriented, and allow creating scalable Client-Server applications even with an Oracle DB system back-end, even with XE2 starter edition (direct access, without any DB.pas / DBExpress layer).