Synopse Open Source

For both our SynOleDB and SynBigTable units, we allow late-binding of data row values, using a variant and direct named access of properties. Thanks to this unique feature (as far as I know in the Delphi database world),

This allows clear and valid code as such:

var Customer: Variant;
begin
  with Props.Execute(
    'select * from Sales.Customer where AccountNumber like ?',
    ['AW000001%'],@Customer) do
    while Step do
      assert(Copy(Customer.AccountNumber,1,8)='AW000001');
end;

In practice, this code is slower than using a standard property based access, like this:

    while Step do
      assert(Copy(Column['AccountNumber'],1,8)='AW000001');

But the first version, using late-binding of column name, just sounds more natural.

Of course, since it's late-binding, we are not able to let the compiler check at compile time for the column name. If the column name in the source code is wrong, an error will be triggered at runtime only. But it would not be an issue, since it would be the same for the SQL code inserted: it's only executed at runtime (this is one of the benefits of using an ORM, by the way: the ORM will generate correct SQL code for you...).

The default VCL implementation of this late-binding was a bit slow for our purpose.
Since it has to deal with Ole Automation, and because it's fun, we hacked the VCL to provide a lighter and faster version for our custom variant types.

Our ORM framework has been released as version 1.14.

It's mainly a bug-fix release:

• Integrated SQLite3 engine updated to latest version 3.7.7.1;
• Fix several issues about JSON generation layout;
• Enhanced automated User Interface generation for object on-screen edition;
• SynPdf unit now handles Bézier curves from TCanvas, and some CMYK functions; also enhanced PDF/A-1compatibility;
• Some speed enhancements, and new functions for the SynOleDB unit.

In order to let our TSynLog logging class intercept all exceptions, we use the low-level global RtlUnwindProc pointer, defined in System.pas.

Alas, under Delphi 5, this global RtlUnwindProc variable is not existing. The code calls directly the RtlUnWind Windows API function, with no hope of custom interception.

Two solutions could be envisaged:

• Modify the Sytem.pas source code, adding the new RtlUnwindProc variable, just like Delphi 7; 
• Patch the assembler code, directly in the process memory.

The first solution is simple. Even if compiling System.pas is a bit more difficult than compiling other units, we already made that for our Enhanced RTL units. But you'll have to change the whole build chain in order to use your custom System.dcu instead of the default one. And some third-party units (only available in .dcu form) may not like the fast that the System.pas interface changed...

So we used the second solution: change the assembler code in the running process memory, to let call our RtlUnwindProc variable instead of the Windows API.

Our SynPdf unit has been refreshed to the 1.13 version.

• code modifications to compile with Delphi 5 compiler;
• added horizontal scaling for GDI enumeration in case of text kerning (could occur for small fonts);
• fixed "Save when closing with Acrobat Reader X" - thanks to Ondrej for the fix;
• fixed clipping problems and vertical font positioning issue in GDI enumeration - thanks to Ondrej for those corrections!