"Programming with databases" (both printed version and Kindle e-book) is the translated and revised Second Edition of my previous book published in 2015.

This book covers various stages of software development and practical cases of the programming with database management systems. You find different recommendations on the choices of the …

Delphi case

Delphi supports interfaces natively. Any variable of variant type can store an interface like any allowed data types.

program IntfDelphi;

{$APPTYPE CONSOLE}
{$R *.res}

uses
  Classes, SysUtils, Variants;

type
  ITest = interface(IInterface)
    ['{BEDC5E17-2C40-4F7C-8C78-34448F5CE146}']
    procedure Foo(const Msg: string);
  end;

  TestImpl = class(TInterfacedObject, ITest)
  public
    procedure Foo(const Msg …

Pro et contra

I use C++Builder 10.1 (Berlin) that proposes both 'classic' bcc32 compiler and new clang bcc32c. Whether do you rather to use classic compiler or to switch to clang? The answer is not quite simple.

The advantages of new clang compiler:

• more of C++11 language …

Debian distribution doesn't have USB startup disk creator software. However, you can make live USB stick based on Live-DVD ISO from command line.

sudo dd bs=4M if=///.iso of=/dev/sdX && sync

where sdX is the USB device name. Don't use trailing digits like sdb1.

Example

sudo dd bs …

The text below is not mine but I completely agree with author, after many years in software engineering using models to generate programs, components and codes. See also Geniel Lamp tool and my presentation "[MDA/MDD approach - Relation to the software development life-cycle](https://www.researchgate.net/publication/287201275_Architecture_of_enterprise_automated_information_system_-Layers_and_levels_-MDA_MDD_approach_-Relation_to_the_software_development_life-cycle".

The …

This article is used in my book "Programming with databases".

Better to see once than to hear a hundred times. This small article explains what are the different kinds of joins in SQL.

At the first time you should take into account that SQL is a declarative 4th generation language …

Since early XE versions C++ Builder supports Delphi units directly added in C++ project and compiles them as well as C/C++ source. However, this approach has several drawbacks:

• Usually, Delphi files are stored in separated folders of other applications and packages. So your C++ project will point to many …

Here are some examples of SQL to generate a sequence of numeric (integer) values from 0 to 99.

ANSI-compatible

SELECT ones.n1 + tens.n2 * 10
FROM
(
  SELECT 0 AS n1
  UNION SELECT 1 AS n1
  UNION SELECT 2 AS n1
  UNION SELECT 3 AS n1
  UNION SELECT 4 AS n1 …

Some countries have integer numbers printed on the transport tickets, for example, in ex-USSR. The ticket is "happy" when the sum of the first half of digits equals to the second one. Then you should eat it and make a wish.

Example:

123456 and 111222 are not happy tickets
123123 …

How to install and use Delphi 7 and help files on Windows 8/10 or Server 2012.

Installation

Start Delphi setup and install all required items including help files.

In Windows 8/10/Server 2012 or later (should work on Windows 7 too):

• Create the shortcut to Delphi32.exe
• Open …