user: Question: What was the rating/share for 18-49 for the episode that had 5.90 million viewers? 
Columns: ['No.', 'Episode', 'Rating', 'Share', 'Rating/share (18-49)', 'Viewers (millions)', 'Rank (timeslot)', 'Rank (night)']
Types: ['real', 'text', 'text', 'real', 'text', 'text', 'real', 'real']
Sample row: [1.0, '"Sarah Jessica Parker"', '4.6', 8.0, '1.6/6', '6.85', 2.0, 5.0]
SQL:

assistant: SELECT "Rating/share (18-49)" FROM "Table" WHERE "Viewers (millions)" = '5.90';