# Database URLs

## What is a Database URL?

The `Database URL` is the connection string of a database.

By default in Zuar Runner, it is the local database (`postgresql://db/analytics`).

The structure of database connection strings is as follows:

`{driver}://{username}:{password}@{server}:{port}/{database}?{parameters}`

## Common Database Drivers
| DBMS | Driver |
|---|------- |
| Amazon Redshift  | redshift+psycopg2 |
| Google BigQuery  | bigquery |
| IBM | DB2db2+ibm_db |
| MariaDB | mysql+pymysql |
| MySQL | mysql+pymysql |
| PostgreSQL | postgresql |
| SQL Server | mssql+pyodbc |
| Snowflake | snowflake |


## Parameters
| DBMS | Parameter |
|--|--|
| SQL Server | ?driver=ODBC+Driver+17+for+SQL+Server |
| Snowflake | ?warehouse={warehouse}


## Encrypted Credentials

In most database url strings, you are required to pass a username and
password through the string. Zuar Runner's [Credential
manager](/user-interface/index.html#credentials) is a way to encrypt and store
credentials to that they don't need to be explicitly included in the
database url string.

To use saved credentials:

Navigate to the Credential manager via the Zuar Runner UI.
	
.. image:: assets/database_urls__credentials.png
   :alt: Zuar Runner Credential Manager image

Select **Add Credentials** and from the dropdown choose `Basic`
Credential type. Give the credential an easy to use name like "mysql"
or "psql". Fill in the `username` and `password` input with the
database credentials. **SAVE!**

.. image:: assets/database_urls__basic_creds.png
   :alt: Zuar Runner Basic Credential

Next, create a **Query** job from the **Add Job** menu. On the
**Connect** screen, deselect **Use default database URI** which
should expose and input for **Database URL**. Input the Database URL
string associated with the type of database you are connecting to and
use the Credential Name created in the previous step instead including
them in the string. For example, if you are trying to query a
PostgreSQL Database, the string would look like
`postgresql://psql@<hostname of database>/<database name>`

Check the **Use credentials** box and it should expose a dropdown
selector. This is where you will selected the saved credential from
the previous step. 

Lastly, write your desired [query in the query input window](/jobs/query/).

.. image:: assets/database_urls__connect.png
   :alt: Connect to database

.. NOTE::

   In order for Zuar Runner to access most databases, it will likely
   need to have access via it's IP address or some other security
   mechanism implemented by your organization. Contact IT to determine
   the best way to allow Zuar Runner access to the source database.

   To get the IP address of your Zuar Runner instance, use your command line 
   and run `nslookup <mitto hostname>` . Based on the example above you 
   would run `nslookup zuar.net`



Once you've completed the Wizard for the Query job. The input section
of the JSON configuration will look something like:

```
    json
      input: {
        use: query.io#QueryInput
        query: SELECT * FROM demo.test_orders;
        dbo: postgresql://psql@zuar.net/analytics
        stream_results: 50000
        credentials: psql
    }
```