In order to test and run the code examples you will need a working instance of PostgreSQL 11 or greater. In particular, it is required that you have a working client (such as psql), a user account, and a database you can work on.

In order to test Perl examples you will need a recent installation of Perl 5, and a Java 8 JDK to compile and run Java examples.

Any other specific requirements will be detailed in the chapters.

You can download the example code files for this book from your account at www.packt.com. If you purchased this book elsewhere, you can visit www.packt.com/support and register to have the files emailed directly to you.

You can download the code files by following these steps:

1. Log in or register at www.packt.com.
2. Select the SUPPORT tab.
3. Click on Code Downloads & Errata.
4. Enter the name of the book in the Search box and follow the onscreen instructions.

Once the file is downloaded, please make sure that you unzip or extract the folder using the latest version of:

• WinRAR/7-Zip for Windows
• Zipeg/iZip/UnRarX for Mac
• 7-Zip/PeaZip for Linux

The code bundle for the book is also hosted on GitHub at https://github.com/PacktPublishing/PostgreSQL-11-Quick-Start-Guide. In case there's an update to the code, it will be updated on the existing GitHub repository.

We also have other code bundles from our rich catalog of books and videos available at https://github.com/PacktPublishing/. Check them out!

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "Mount the downloaded WebStorm-10*.dmg disk image file as another disk in your system."

A block of code is set as follows:

ImgRes* new_ImgRes() {
  ImgRes* new_object = (ImgRes*) palloc( sizeof( ImgRes ) );
  new_object->h_px = 300;
  new_object->v_px = 300;
  new_object->dpi  = 96;
  return new_object;
}

char* to_string( ImgRes* object ){

return psprintf( TEXT_PATTERN,
                   object->h_px,  object->v_px,  object->dpi );
}

Any command-line input or output is written as follows:

testdb=> CREATE TYPE t_media_file_type
AS ENUM ( 'audio', 'image', 'text' );

Bold: Indicates a new term, an important word, or words that you see onscreen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "Select System info from the Administration panel."