# PostgreSQL

Using the Postgres storage engine you can use any Postgres based database as your ngSurvey backend. 

## Requirements

To install  ngSurvey on a Postgres database you will need to meet following requirements

1. Postgres version 16.x or above.
2. User used to connect to the Postgres server must have enough privileges to to create a new database. 

## NGSurvey configuration

In order to configure ngSurvey to work with Postgres you need to setup following environment variables.

{% hint style="info" %}
NGSurvey will automatically create or update the database that you have specified in the connection string. By default ngSurvey will use "postgres" as the maintenance database if you would like to change the maintenance database that is used during creation of the new ngsurvey database you can change it using following environment variable : NGSurvey:PGMaintenanceDB
{% endhint %}

* **`ConnectionStrings:NGSurveyDB`** holds your connection string to your Postgres server.
* **`NGSurvey:StorageEngine`** must be set to *Postgres.*

## Entra Managed Identity

To use an Entra Managed Identity to authenticate your connection to Postgres, you may specify the set the Entra username in the PostgreSQL connection string without any passwords. Ensure this user has the proper access rights in your PostgreSQL database and that you are using a Flexible Server Host for your PostgreSQL database.

## Health check

Once you have configured your database settings you may re-start the web service hosting ngSurvey. NGSurvey will automatically setup the database will all the required tables.

You may also check if your installation is properly setup using following link :\
<https://yourrootsite/api/system/status>


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