What is the percentage of double bonds in the molecule TR008?
double bond refers to bond_type = ' = '; TR008 is the molecule id; percentage = DIVIDE(SUM(bond_type = ' = '), COUNT(bond_id)) as percent where molecule_id = 'TR008'
SELECT CAST(COUNT(CASE WHEN T.bond_type = '=' THEN T.bond_id ELSE NULL END) AS REAL) * 100 / COUNT(T.bond_id) FROM bond AS T WHERE T.molecule_id = 'TR008'