Improved "Choosing database" documentation page

Author: jbtronics

docs/installation/choosing_database.md

@@ -7,40 +7,96 @@ nav_order: 1
 
 # Choosing database: SQLite or MySQL
 
-Part-DB saves its data in a [relational (SQL) database](https://en.wikipedia.org/wiki/Relational_database). Part-DB
-supports either the use of [SQLite](https://www.sqlite.org/index.html)
-or [MySQL](https://www.mysql.com/) / [MariaDB](https://mariadb.org/) (which are mostly the same, except for some minor
-differences).
+Part-DB saves its data in a [relational (SQL) database](https://en.wikipedia.org/wiki/Relational_database).
+
+For this multiple database types are supported, currently these are:
+
+* [SQLite](https://www.sqlite.org/index.html)
+* [MySQL](https://www.mysql.com/) / [MariaDB](https://mariadb.org/) (which are mostly the same, except for some minor
+  differences)
+* [PostgreSQL](https://www.postgresql.org/)
+
+All these database types allow for the same basic functionality and allow Part-DB to run. However, there are some minor
+differences between them, which might be important for you. Therefore the pros and cons of the different database types
+are listed here.
 
 {: .important }
 You have to choose between the database types before you start using Part-DB and **you can not change it (easily) after
 you have started creating data**. So you should choose the database type for your use case (and possible future uses).
 
 ## Comparison
 
-**SQLite** is the default database type which is configured out of the box. All data is saved in a single file (
-normally `var/app.db` in the Part-DB folder) and no additional installation or configuration besides Part-DB is needed.
-To use **MySQL/MariaDB** as database, you have to install and configure the MySQL server, configure it and create a
-database and user for Part-DB, which needs some additional work. When using docker you need an additional docker
-container, and volume for the data
+### SQLite
+
+#### Pros
+
+* **Easy to use**: No additional installation or configuration is needed, just start Part-DB and it will work out of the box
+* **Easy backup**: Just copy the SQLite file to a safe place, and you have a backup, which you can restore by copying it
+  back. No need to work with SQL dumps
+
+#### Cons
+
+* **Performance**: SQLite is not as fast as MySQL or PostgreSQL, especially when using complex queries or many users.
+* **Emulated RegEx search**: SQLite does not support RegEx search natively. Part-DB can emulate it, however that is pretty slow.
+* **Emualted natural sorting**: SQLite does not support natural sorting natively. Part-DB can emulate it, but it is pretty slow.
+* **Limitations with Unicode**: SQLite has limitations in comparisons and sorting of Unicode characters, which might lead to
+  unexpected behavior when using non-ASCII characters in your data. For example `µ` (micro sign) is not seen as equal to 
+  `μ` (greek minuscule mu), therefore searching for `µ` (micro sign) will not find parts containing `μ` (mu) and vice versa.
+  The other databases behave more intuitive in this case.
+* **No advanced features**: SQLite do no support many of the advanced features of MySQL or PostgreSQL, which might be utilized
+  in future versions of Part-DB
+
+
+### MySQL/MariaDB
+
+**If possible, it is recommended to use MariaDB 10.7+ (instead of MySQL), as it supports natural sorting of columns natively.**
+
+#### Pros
+
+* **Performance**: Compared to SQLite, MySQL/MariaDB will probably perform better, especially in large databases with many
+  users and high activity.
+* **Natural Sorting**: MariaDB 10.7+ supports natural sorting of columns. On other databases it has to be emulated, which is pretty
+  slow.
+* **Native RegEx search**: MySQL supports RegEx search natively, which is faster than emulating it in PHP.
+* **Advanced features**: MySQL/MariaDB supports many advanced features, which might be utilized in future versions of Part-DB.
+* **Full Unicode support**: MySQL/MariaDB has better support for Unicode characters, which makes it more intuitive to use
+  non-ASCII characters in your data.
+
+#### Cons
+
+* **Additional installation and configuration**: You have to install and configure the MySQL server, create a database and
+  user for Part-DB, which needs some additional work compared to SQLite.
+* **Backup**: The MySQL database has to be dumped to a SQL file (using `mysqldump`). The `console partdb:backup` command can automate this.
+
+
+### PostgreSQL
 
-When using **SQLite** The database can be backuped easily by just copying the SQLite file to a safe place. Ideally, the *
-*MySQL** database has to be dumped to a SQL file (using `mysqldump`). The `console partdb:backup` command can do this
-automatically
+#### Pros
+* **Performance**: PostgreSQL is known for its performance, especially in large databases with many users and high activity.
+* **Advanced features**: PostgreSQL supports many advanced features, which might be utilized in future versions of Part-DB.
+* **Full Unicode support**: PostgreSQL has better support for Unicode characters, which makes it more intuitive to use
+  non-ASCII characters in your data.
+* **Native RegEx search**: PostgreSQL supports RegEx search natively, which is faster than emulating it in PHP.
+* **Native Natural Sorting**: PostgreSQL supports natural sorting of columns natively in all versions and in general the support for it
+  is better than on MariaDB.
+* **Support of transactional DDL**: PostgreSQL supports transactional DDL, which means that if you encounter a problem during a schema change,
+the database will automatically rollback the changes. On MySQL/MariaDB you have to manually rollback the changes, by restoring from a database backup.
 
-However, SQLite does not support certain operations like regex search, which has to be emulated by PHP and therefore is
-pretty slow compared to the same operation at MySQL. In the future, there might be features that may only be available, when
-using MySQL. Also, SQLite has limitations in comparisons and sorting of Unicode characters, which might lead to unexpected
-behavior when using non-ASCII characters in your data. For example `µ` (micro sign) is not seen as equal to `μ(greek minuscule mu),
-therefore searching for `µ` (micro sign) will not find parts containing `μ` (mu) and vice versa. In MySQL identical-looking characters are seen as equal, which is more intuitive in most cases.
+#### Cons
+* **New backend**: The support of postgresql is new, and it was not tested as much as the other backends. There might be some bugs caused by this.
+* **Additional installation and configuration**: You have to install and configure the PostgreSQL server, create a database and
+  user for Part-DB, which needs some additional work compared to SQLite.
+* **Backup**: The PostgreSQL database has to be dumped to a SQL file (using `pg_dump`). The `console partdb:backup` command can automate this.
 
-In general MySQL might perform better for big Part-DB instances with many entries, lots of users and high activity, than
-SQLite.
 
-## Conclusion and Suggestion
+## Recommendation
 
 When you are a hobbyist and use Part-DB for your own small inventory management with only you as user (or maybe sometimes
-a few other people), then the easy-to-use SQLite database will be fine.
+a few other people), then the easy-to-use SQLite database will be fine, as long as you can live with the limitations, stated above.
+However using MariaDB (or PostgreSQL), has no disadvantages in that situation (besides the initial setup requirements), so you might
+want to use it, to be prepared for future use cases.
 
-When you are planning to have a very big database, with a lot of entries and many users which regularly (and
-concurrently) using Part-DB you should maybe use MySQL as this will scale better.
+When you are planning to have a very big database, with a lot of entries and many users which regularly using Part-DB, then you should
+use MariaDB or PostgreSQL, as they will perform better in that situation and allow for more advanced features.
+If you should use MariaDB or PostgreSQL depends on your personal preference and what you already have installed on your servers and 
+what you are familiar with.