user: Question: What is the episode number that has production code 8ABX15?
Columns: ['No. in set', 'No. in series', 'Title', 'Directed by', 'Written by', 'Original air date', 'Production code']
Types: ['real', 'real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 174.0, '" Per Manum "', 'Kim Manners', 'Chris Carter & Frank Spotnitz', 'February18,2001', '8ABX13']
SQL:

assistant: SELECT "No. in series" FROM "Table" WHERE "Production code" = '8ABX15';