user: Question: When the gdp (ppp, in billions of current international dollars) is 7.93, what is the maximum ppp gdp per emissions (in international dollars per ton)?
Columns: ['Country', 'Annual CO2 emissions (in thousands of metric tons)', 'GDP (current, in billions of US dollars)', 'GDP per Emissions (in US dollars per ton)', 'GDP (PPP, in billions of current international dollars)', 'PPP GDP per Emissions (in international dollars per ton)']
Types: ['text', 'real', 'text', 'real', 'text', 'real']
Sample row: ['Chad', 396.0, '6.31', 15924.0, '15.40', 38881.0]
SQL:

assistant: SELECT MAX("PPP GDP per Emissions (in international dollars per ton)") FROM "Table" WHERE "GDP (PPP, in billions of current international dollars)" = '7.93';