why sql over text file saving systems

hi.

i use sql for saving system but i need some advantages and disadvantages of it. in comparison to text file based saving system because my friend is not impressed to use it and i want him to use it. can some one please list some of them.

thanks.

and some questions:
1. what limit we have in samp sqlite and what feature are not in samp sqlite
2. any way we can have that in samp?
3. any way to make sqlite error logging more precise