Establishing a Connection
With the CData Cmdlets users can install a data module, set the connection properties, and start scripting. This section provides examples of using our EnterpriseDB Cmdlets with native PowerShell cmdlets, like the CSV import and export cmdlets.
Installing and Connecting
If you have PSGet, installing the cmdlets can be accomplished from the PowerShell Gallery with the following command. You can also obtain a setup from the CData site.
Install-Module EnterpriseDBCmdlets
The following line is then added to your profile, loading the cmdlets on the next session:
Import-Module EnterpriseDBCmdlets;
You can then use the Connect-EnterpriseDB cmdlet to create a connection object that can be passed to other cmdlets:
$conn = Connect-EnterpriseDB -User 'postgres' -Password 'admin' -Server '127.0.0.1' -Port '5444' -Database 'postgres'
Connecting to EnterpriseDB
The following connection properties are required in order to connect to data.
- User: The user which will be used to authenticate with the EnterpriseDB server.
- Password: The password which will be used to authenticate with the EnterpriseDB server.
- Server: The host name or IP of the server hosting the EnterpriseDB database.
- Port: The port of the server hosting the EnterpriseDB database.
You can also optionally set the following:
- Database: The default database to connect to when connecting to the EnterpriseDB Server. If this is not set, the user's default database will be used.
Retrieving Data
After you have created a connection, you can use the other cmdlets to perform operations that you would normally expect to be able
to perform against a relational database. The Select-EnterpriseDB cmdlet provides a native PowerShell interface for retrieving data:
$results = Select-EnterpriseDB -Connection $conn -Table ""postgres"."public".Orders" -Columns @("ShipName, ShipCity") -Where "ShipCountry='USA'"The Invoke-EnterpriseDB cmdlet provides an SQL interface. This cmdlet can be used to execute an SQL query via the Query parameter.
Piping Cmdlet Output
The cmdlets return row objects to the pipeline one row at a time. The following line exports results to a CSV file:
Select-EnterpriseDB -Connection $conn -Table "postgres"."public".Orders -Where "ShipCountry = 'USA'" | Select -Property * -ExcludeProperty Connection,Table,Columns | Export-Csv -Path c:\my"postgres"."public".OrdersData.csv -NoTypeInformation
You will notice that we piped the results from Select-EnterpriseDB into a Select-Object cmdlet and excluded some properties before piping them into an Export-CSV cmdlet. We do this because the CData Cmdlets append Connection, Table, and Columns information onto each row object in the result set, and we do not necessarily want that information in our CSV file.
However, this makes it easy to pipe the output of one cmdlet to another. The following is an example of converting a result set to JSON:
PS C:\> $conn = Connect-EnterpriseDB -User 'postgres' -Password 'admin' -Server '127.0.0.1' -Port '5444' -Database 'postgres' PS C:\> $row = Select-EnterpriseDB -Connection $conn -Table ""postgres"."public".Orders" -Columns (ShipName, ShipCity) -Where "ShipCountry = 'USA'" | select -first 1 PS C:\> $row | ConvertTo-Json { "Connection": { }, "Table": ""postgres"."public".Orders", "Columns": [ ], "ShipName": "MyShipName", "ShipCity": "MyShipCity" }
Deleting Data
The following line deletes any records that match the criteria:
Select-EnterpriseDB -Connection $conn -Table "postgres"."public".Orders -Where "ShipCountry = 'USA'" | Remove-EnterpriseDB
Modifying Data
The cmdlets make data transformation easy as well as data cleansing. The following example loads data from a CSV file into EnterpriseDB, checking first whether a record already exists and needs to be updated instead of inserted.
Import-Csv -Path C:\My"postgres"."public".OrdersUpdates.csv | %{ $record = Select-EnterpriseDB -Connection $conn -Table "postgres"."public".Orders -Where ("Id = `'"+$_.Id+"`'") if($record){ Update-EnterpriseDB -Connection $conn -Table "postgres"."public".Orders -Columns @("ShipName","ShipCity") -Values @($_.ShipName, $_.ShipCity) -Where "Id = `'$_.Id`'" }else{ Add-EnterpriseDB -Connection $conn -Table "postgres"."public".Orders -Columns @("ShipName","ShipCity") -Values @($_.ShipName, $_.ShipCity) } }