# GATE Papers >> CSE >> 2014 >> Question No 231

Question No. 231

What is the optimized version of the relation algebra expression ${\pi }_{A1}\left({\mathrm{\pi }}_{A2}\left({\mathrm{\sigma }}_{F1}\left({\mathrm{\sigma }}_{F2}\left(r\right)\right)\right)\right),$ where A1, A2 are sets of attributes in r with A1 ⊂ A2 and F1, F2 are Boolean expressions based on the attributes in r?