## 18.2. Installing PostgreSQL for 1C on Windows

PostgreSQL offers the following installation modes for the supported Windows systems:

- GUI installation using an interactive wizard

- Command-line installation

Additionally, you have to set up the environment for using PL/Perl and PL/Python, if these procedural languages are required for your purposes. For details, see Section 18.2.4.

To avoid confusion, note that there are the following different users on Windows systems:

- PostgreSQL installation is performed on behalf of an operating system user. All the database files belong to this user.

- You must connect to the database cluster on behalf of the user created at installation time to be able to work with the database. This is not an operating system user.

- By default, PostgreSQL service is started on behalf of `NT AUTHORITY\NetworkService`, which is a special Windows Service Account. You can specify another Windows user for starting PostgreSQL service in the corresponding text box of the installer, if required. The provided user must have the right to start Windows services.

### 18.2.1. Supported Windows Versions

PostgreSQL is available for the following 64-bit Windows versions:

- Windows 8.1, 10

- Windows Server 2008 R2 or higher

### 18.2.2. GUI Installation

PostgreSQL provides an installer with an interactive wizard that configures and installs PostgreSQL, creates the default database, and enables server autostart.

To install PostgreSQL, run the provided installer as administrator and follow the on-screen instructions. Make sure to take into account the following installation specifics:

- You can install all the PostgreSQL components, or customize the installation by excluding server or developer components. Client utilities are always installed.

- The selected data directory must be empty. Otherwise, PostgreSQL cannot create the default database. The default data directory is `C:\Program Files\PostgresPro\12\data`.

- If the Allow external connections check box is selected (default), the installer modifies `postgresql.conf` and `pg_hba.conf` files to allow external connections. Otherwise, PostgreSQL server is listening for connections from the localhost only. If you decide to enable external connections when the installation is complete, you have to modify the Windows Firewall configuration to allow PostgreSQL server to accept connections.

- Make sure to remember the username and password you set up when installing PostgreSQL as it will be required to connect to the PostgreSQL server when using password-based authentication methods.

- By default, PostgreSQL uses `icu` collations. If you are upgrading an installation with the default collation provided by `libc`, such as PostgreSQL, make sure to choose `libc` collation provider in the corresponding drop-down list of the installer.

- PostgreSQL provides a pre-configured psql that you can launch from the Start menu, so you do not have to configure the standard environment variables. However, if you would like to work with PostgreSQL from the standard command prompt without specifying full paths to the binary files, select the Set up environment variables check box.

Once the installation completes, your PostgreSQL instance is ready to use, with server autostart enabled. If you need more than one PostgreSQL instance on the same system, you have to configure them manually. For details, see Section 18.2.5.

### 18.2.3. Command-Line Installation

To install PostgreSQL from the command line, run the downloaded installer file passing one or more options described in Section 18.2.3.1.

#### 18.2.3.1. Command-Line Options

Installation directory path:

    /D=path

Silent install:

    /S

`INI` file that provides the options to customize the server installation:

    /init=ini_file_name

If you would like to customize the installation, you must create the `INI` file manually, as described in Section 18.2.3.2.

#### 18.2.3.2. INI File Format

You can add the following installation options to the [options] section of the INI file:

- `InstallDir` — path where to install server. If you specified the /D option on the command line, it will be overwritten by the `InstallDir` value.

- `DataDir` — path where to create default database

- `Port` — TCP/IP port to listen. Default: 5432.

- `SuperUser` — name of the database user who will have admin rights in the database

- `Password` — password of the user

- `noExtConnections = 1` — do not allow external connections

- `Coding = UNICODE` — character encoding to use in the database

- `Locale` — locale to use in the database. There can be several different locales for each encoding

- `Vcredist = no` — do not install Visual C redistributable libraries (use it only if these libraries are already installed on your system)

- `envvar = 1` — set up environment variables helpful for PostgreSQL: `PGDATA`, `PGDATABASE`, `PGUSER`, `PGPORT`, `PGLOCALEDIR`

- `needoptimization = 0` — disable automatic tuning of configuration parameters based on the available system resources.

- `datachecksums = 0` — disable data checksums for the cluster.

- `serviceaccount` — specify a Windows user for starting PostgreSQL service. The provided user must have the right to start Windows services. By default, PostgreSQL service is started on behalf of `NT AUTHORITY\NetworkService`, which is a special Windows Service Account.

- `servicepassword` — provide the password for the Windows user specified in the `serviceaccount` option.

- `serviceid` — change PostgreSQL service name.

- `islibc = 1` — use `libc` as the default collation provider.

### 18.2.4. Loading Procedural Languages

PostgreSQL distribution for Windows systems includes `PL/Perl` and `PL/Python` procedural languages.

#### 18.2.4.1. Setting up the Environment for PL/Python

To configure the system for using PL/Python, complete the following steps:

1. Download and install the latest available version of Python 2.7 for Windows. Choose the 64-bit version as PostgreSQL server has 64-bit architecture type. You can find the installers at https://www.python.org/.

2. Create the PL/Python extension by running the following command in psql:

       CREATE EXTENSION plpythonu

### Tip

In some cases, when you create a PL/Python function, the connection to the server is lost and the server log shows the following error message:

    ImportError: module site not found

To avoid this issue, try to specify the Python installation directory in the `PYTHONHOME` environment variable and restart the PostgreSQL service.

#### 18.2.4.2. Setting up the Environment for PL/Perl

To configure the system for using PL/Perl, complete the following steps:

1. Download and install ActivePerl 5.26 from https://www.activestate.com/activeperl/downloads.

2. Make sure to select the Add Perl to the PATH environment variable option in the installation wizard.

3. Restart the PostgreSQL server.

4. Create the PL/Perl extension by running the following command in psql:

       CREATE EXTENSION plperlu

### 18.2.5. Configuring Multiple PostgreSQL Instances

To set up several PostgreSQL server instances with different data directories on Windows, do the following:

1. Install PostgreSQL as explained in Section 18.2.2 or Section 18.2.3. The installed binary files are shared by all PostgreSQL instances, so you need to complete this step only once.

2. Select an empty folder that your new PostgreSQL instance will use as the data directory. For example, `C:\Program Files\PostgresPro\12\data2`. Make sure to grant Full Control permissions for this folder to the current OS user that will own the database files and the user on behalf of which the server is running (`NT AUTHORITY\NetworkService` by default).

3. Run initdb specifying the path to the new data directory and any other parameters required to initialize another server instance. For example:

       "C:\Program Files\PostgresPro\12\bin\initdb.exe" --encoding=UTF8 -U "postgres" -D "C:\Program Files\PostgresPro\12\data2"

   Alternatively, you can stop the running server and copy the contents of the existing data directory into the newly created folder. In this case, the new PostgreSQL instance inherits all the settings of the original instance, including authentication settings.

4. Modify `postgresql.conf` settings for the new PostgreSQL instance as required. Make sure to specify different ports for your server instances to avoid conflicts.

5. Open the command prompt as Administrator and register a new PostgreSQL service with a unique name, for example, `postgrespro-data2`:

       "C:\Program Files\PostgresPro\12\bin\pg_ctl.exe" register -N "postgrespro-data2" -U "NT AUTHORITY\NetworkService" -D "C:\Program Files\PostgresPro\12\data2" -w

   Start the registered service:

       sc start "postgrespro-data2"

Once the service is started, your PostgreSQL instance is ready to use. If you need any additional PostgreSQL extensions, make sure to enable them for the new instance as explained in Section 18.3.

### 18.2.6. Uninstalling PostgreSQL for 1C

The procedure of uninstalling PostgreSQL for 1C depends on the number of PostgreSQL instances set up on your system.

If you have a single PostgreSQL instance created at installation time, you only need to run the `C:\Program Files\PostgresPro\12\uninstall.exe` program. This program automatically stops the server and unregisters the service for this instance.

If you have created any additional PostgreSQL instances, you have to complete the following steps:

1. Stop the server for each instance:

       "C:\Program Files\PostgresPro\12\bin\pg_ctl.exe" stop -D "C:\Program Files\PostgresPro\12\data_dir" -m fast -w

2. Unregister the service for each instance:

       "C:\Program Files\PostgresPro\12\bin\pg_ctl.exe" unregister -N "postgrespro_service_name"

3. Run the `C:\Program Files\PostgresPro\12\uninstall.exe` to uninstall PostgreSQL binary files.