Update README.md

Author: NikolayS

README.md

@@ -1,18 +1,59 @@
 # PostgresDBA
 Useful tools for Postgres DBA
 
+## Requirements
+
 ## Installation
 Clone, go to the directory and run psql (version 10 is required):
 ```bash
 git clone git@github.com:NikolayS/PostgresDBA.git
 cd PostgresDBA
-psql
 ```
 
-In psql, type:
+That's it. Nothing is really needed to be installed.
+
+## Usage
+
+### Locally
+If you are running psql and Postgres server on the same machine, just launch psql:
+```bash
+psql -U <username> <dbname>
+```
+
+And type (assuming that you are sitting in the `PostgresDBA` directory):
 ```
-\i start.psql
+\i ./start.psql
 ```
 
 – it will open interactive menu.
 
+### Remotely
+What to do if you need to connect to a remote Postgres server? Usually, Postgres is behind firewall and/or doesn't listen to a public netowork interface. So you need to be able to connect to the sever using SSH. If you can do it, then just create SSH tunnel (assuming that Postgres listens to default port 5432 on that server:
+
+```bash
+ssh -rNTML 9432:localhost:5432 you-server.com
+```
+
+Then, just launch psql, connecting to port 9432 at localhost:
+```bash
+psql -h localhost -p 9432 -U <username> <dbname>
+```
+
+Then you are ready to use it (again, assuming you were sitting in the project directory when launching psql; otherwise, use absolute path):
+```
+\i ./start.psql
+```
+
+### Heroku
+Sitting in the `PostgresDBA` directory on your local machine, run, as usual:
+```bash
+heroku pg:psql -a <your_project_name>
+```
+
+And then, in psql:
+```
+\i ./start.psql
+```
+
+## Uninstallation
+No steps are needed, just delete PostgresDBA directory.