user: Question: What districts of Bihar have a sex ratio in 1991 of 864?
Columns: ['Districts of Bihar', 'Total Population 2001', 'Male Population 2001', 'Female Population 2001', 'Growth Rate 1981-91', 'Growth Rate 1991-01', 'Sex Ratio ‡ 1991', 'Sex Ratio ‡ 2001', 'Population density † 1991', 'Population density † 2001']
Types: ['text', 'real', 'real', 'real', 'text', 'text', 'real', 'real', 'real', 'real']
Sample row: ['West Champaran', 3043044.0, 1600853.0, 1442191.0, '18.30', '30.40', 877.0, 901.0, 446.0, 582.0]
SQL:

assistant: SELECT "Districts of Bihar" FROM "Table" WHERE "Sex Ratio ‡ 1991" = 864.0;