Thank you very much, Aaron, for you detailed advice!

However, I didn't find the Facility Net Purchased Electric Energy output variable in the .sql output file following your suggestion by adding the following line in the IDF file:

Output:SQLite, SimpleAndTabular;

... and it seems Facility Net Purchased Electric Energy is not shown in the sql database when it's opened and queried in SQLiteStudio.

Nevertheless, as your suggested, once the I'll try to specify purchased electricity related variables are specified variable through output:variable and output:meter, they are shown in the sql database, although I haven't figured out how the cumulative values are calculated and reported. as you suggested.

Thanks.