Hui-improve-README.md (#56)

More detail on installation.

Co-authored-by: Lan Hui <1348141770@qq.com>
Reviewed-on: http://121.4.94.30:3000/mrlan/LRR/pulls/56
Co-authored-by: mrlan <mrlan@noreply.121.4.94.30>
Co-committed-by: mrlan <mrlan@noreply.121.4.94.30>

README.md

@@ -18,15 +18,17 @@ Our mission is to make the experience of submitting assignments great for tens o
 # Installation Instructions
 
 
-## Hui's steps
+## Hui steps
 
 I spent about two hours installing LRR to a bare, remote Ubuntu server (Ubuntu 20.04 LTS).
 
-LRR needs Apache and MySQL to run.  I followed [How To Install Linux, Apache, MySQL, PHP (LAMP) stack on Ubuntu 20.04](https://www.digitalocean.com/community/tutorials/how-to-install-linux-apache-mysql-php-lamp-stack-on-ubuntu-20-04) to set up these server applications.
+LRR needs Apache and MySQL to run.  I followed [How To Install Linux, Apache, MySQL, PHP (LAMP) stack on Ubuntu 20.04](https://www.digitalocean.com/community/tutorials/how-to-install-linux-apache-mysql-php-lamp-stack-on-ubuntu-20-04) to set up these server applications.  [How to install and configure PHP](https://ubuntu.com/server/docs/programming-php) is also a good guide.
 
-LRR uses a database called `lrr`.  I need to export the existing `lrr` to a plain text file (including many sql commands) and import that text file to the newly created `lrr` database on the new server.
+LRR uses a database called `lrr`.  So create this database using MySQL root account.  Open MySQL's prompt using `sudo mysql`.  Create the database using command `CREATE DATABASE lrr;`, and grant all privileges to MySQL user `lrr` using command `GRANT ALL PRIVILEGES ON lrr.* TO 'mnc'@'localhost' WITH GRANT OPTION;`.   If MySQL user mnc does not exist, create it using command `CREATE USER 'mnc'@'localhost' IDENTIFIED BY 'password'`.
-The command for exporting the database is `mysqldump -u mnc -p lrr > lrr_database_dump.txt`.
+
-The command for importing is `mysql -u mnc -p lrr < lrr_database_dump.txt`.  Read [How to Import and Export MySQL Databases in Linux](https://phoenixnap.com/kb/import-and-export-mysql-database) for more detail.
+To facilitate data migration, I need to export the existing `lrr` to a plain text file (including many sql commands) and import that text file to the newly created `lrr` database on the new server.
+The command for exporting the database is `mysqldump -u mnc -p lrr > lrr_database_dump.txt`, where mnc after -u is MySQL's username, and lrr after -p is the database name.
+The command for importing is `mysql -u mnc -p lrr < lrr_database_dump.txt`.  Read [How to Import and Export MySQL Databases in Linux](https://phoenixnap.com/kb/import-and-export-mysql-database) for more detail. Do not have lrr_database_dump.txt?  You can use lrr_database.sql in this repo instead.
 
 LRR also needs to store assignment submissions.  We store them in a folder called `../../lrr_submission`.  Note that `lrr_submission` is two levels above the project folder (where many PHP files reside).  I copied this folder from the existing one.  I think it is also OK if you create an empty folder.   
 We need to set a proper owner and accessibility for `lrr_submission` using the following two commands:
@@ -49,7 +51,7 @@ Enable the site lrr: `sudo a2ensite lrr`.  Restart the apache server: `sudo syst
 Visit the LRR application by entering this URL in a web browser: http://121.4.94.30/.
 
 
-## Enock's steps
+## Enock steps
 
 Enock, a graduate student here, has made a tutorial about how he deployed LRR to a remote server (http://lanlab.org/course/2021s/spm/PuTTY-Server.txt).