Replicate PostgreSQL Data from PowerShell



The CData ODBC Driver for PostgreSQL enables out-of-the-box integration with Microsoft's built-in support for ODBC. The ODBC driver instantly integrates connectivity to the real PostgreSQL data with PowerShell.

You can use the .NET Framework Provider for ODBC built into PowerShell to quickly automate integration tasks like replicating PostgreSQL data to other databases. This article shows how to replicate PostgreSQL data to SQL Server in 5 lines of code.

You can also write PowerShell code to execute create, read, update, and delete (CRUD) operations. See the examples below.

Create an ODBC Data Source for PostgreSQL

If you have not already, first specify connection properties in an ODBC DSN (data source name). This is the last step of the driver installation. You can use the Microsoft ODBC Data Source Administrator to create and configure ODBC DSNs.

To connect to PostgreSQL, set the Server, Port (the default port is 5432), and Database connection properties and set the User and Password you wish to use to authenticate to the server. If the Database property is not specified, the data provider connects to the user's default database.

SSH Connectivity for PostgreSQL

You can use SSH (Secure Shell) to authenticate with PostgreSQL, whether the instance is hosted on-premises or in supported cloud environments. SSH authentication ensures that access is encrypted (as compared to direct network connections).

SSH Connections to PostgreSQL in Password Auth Mode

To connect to PostgreSQL via SSH in Password Auth mode, set the following connection properties:

• User: PostgreSQL User name
• Password: PostgreSQL Password
• Database: PostgreSQL database name
• Server: PostgreSQL Server name
• Port: PostgreSQL port number like 3306
• UserSSH: "true"
• SSHAuthMode: "Password"
• SSHPort: SSH Port number
• SSHServer: SSH Server name
• SSHUser: SSH User name
• SSHPassword: SSH Password

SSH Connections to PostgreSQL in Public Key Auth Mode

To connect to PostgreSQL via SSH in Password Auth mode, set the following connection properties:

• User: PostgreSQL User name
• Password: PostgreSQL Password
• Database: PostgreSQL database name
• Server: PostgreSQL Server name
• Port: PostgreSQL port number like 3306
• UserSSH: "true"
• SSHAuthMode: "Public_Key"
• SSHPort: SSH Port number
• SSHServer: SSH Server name
• SSHUser: SSH User name
• SSHClientCret: the path for the public key certificate file

Connect to PostgreSQL

The code below shows how to use the DSN to initialize the connection to PostgreSQL data in PowerShell:

$conn = New-Object System.Data.Odbc.OdbcConnection
$conn.ConnectionString = "DSN=CData PostgreSQL Source x64"

Back Up PostgreSQL Data to SQL Server

After you enable caching, you can use the code below to replicate data to SQL Server.

Set the following connection properties to configure the caching database:

• CacheProvider: The name of the ADO.NET provider. This can be found in the Machine.config for your version of .NET. For example, to configure SQL Server, enter System.Data.SqlClient.

• CacheConnection: The connection string of properties required to connect to the database. Below is an example for SQL Server:

  Server=localhost;Database=RSB;User Id=sqltest;Password=sqltest;

The SQL query in the example can be used to refresh the entire cached table, including its schema. Any already existing cache is deleted.

$conn.Open()
# Create and execute the SQL Query
$SQL = "CACHE DROP EXISTING SELECT * FROM " + $Orders
$cmd = New-Object System.Data.Odbc.OdbcCommand($sql,$conn)
$count = $cmd.ExecuteNonQuery()
$conn.Close()

The driver gives you complete control over the caching functionality. See the help documentation for more caching commands and usage examples. See the help documentation for steps to replicate to other databases.

Other Operations

To retrieve PostgreSQL data in PowerShell, call the Fill method of the OdbcDataAdapter method. To execute data manipulation commands, initialize the OdbcCommand object and then call ExecuteNonQuery. Below are some more examples CRUD commands to PostgreSQL through the .NET Framework Provider for ODBC:

Retrieve PostgreSQL Data

$sql="SELECT ShipName, ShipCity from Orders"
 
$da= New-Object System.Data.Odbc.OdbcDataAdapter($sql, $conn)
$dt= New-Object System.Data.DataTable
$da.Fill($dt) 
 
$dt.Rows | foreach {
 $dt.Columns | foreach ($col in dt{
 Write-Host $1[$_]
 }
}

Update PostgreSQL Data

$cmd = New-Object System.Data.Odbc.OdbcCommand("UPDATE Orders SET ShipCountry='USA' WHERE Id = @myId", $conn)
$cmd.Parameters.Add(new System.Data.Odbc.OdbcParameter("myId","001d000000YBRseAAH")
$cmd.ExecuteNonQuery()

Insert PostgreSQL Data

$cmd = New-Object System.Data.Odbc.OdbcCommand("INSERT INTO Orders SET ShipCountry='USA' WHERE Id = @myId", $conn)
$cmd.Parameters.Add(new System.Data.Odbc.OdbcParameter("myId","001d000000YBRseAAH")
$cmd.ExecuteNonQuery()

Delete PostgreSQL Data

$cmd = New-Object System.Data.Odbc.OdbcCommand("DELETE FROM Orders WHERE Id = @myid", $conn)
$cmd.Parameters.Add(new System.Data.Odbc.OdbcParameter("myId","001d000000YBRseAAH")
$cmd.ExecuteNonQuery()