From my experience, users prefer accordion menus. There are tons of great examples out there, simply Google "accordion menus UI":
However, to do a deeper dive, especially if you have a mobile project or a demanding client/stakeholder that wants substantiated design decision making, you need to know the following;
- Is your "table" more of a data table that will allow users to select multiple subrows after clicking on the parent row to sort and group various data points?
- Or is it more of a menu that will only allow users to view subrows from parent rows and click the links to follow to the page? (This brings up a whole other discussion on how to display the "table"/menu as users navigate through the different pages it links to -- fixed, accordion, hamburger menu, etc.)
I'm guessing you're looking for a solution for more of a menu-like table.
Google's Material Design advocates for nesting.
Alternatively, an expansion panel might be what you're looking for especially if the table allows users to interact with the subrows.