SQL/ How to display opposite each other records from the database?

Question

SQL

How to retrieve data from database. There is a table with the following columns product_id, language id, name. A selection should be made to match products with the same 'product_id' against each other. An example structure is shown in the image

Answer 1

Rollup is a non-standard operation for relational DBMSs.
Depends on your DBMS.
MS SQL has a PIVOT/UNPIVOT construct, but it's inconvenient to use.