>From my shell session: [[[ % time sqlite3 foo.db "SELECT hash, revision, offset, size, expanded_size FROM rep_cache;" > /dev/null sqlite3 foo.db > /dev/null 12.72s user 0.69s system 98% cpu 13.575 total
% time sqlite3 foo.db "SELECT hash, revision, offset, size, expanded_size FROM rep_cache;" > /dev/null sqlite3 foo.db > /dev/null 12.56s user 0.94s system 99% cpu 13.561 total % time sqlite3 foo.db "SELECT hash, revision, offset, size, expanded_size, COUNT(*) FROM rep_cache;" > /dev/null sqlite3 foo.db > /dev/null 2.76s user 0.72s system 99% cpu 3.492 total % time sqlite3 foo.db "SELECT hash, revision, offset, size, expanded_size, COUNT(*) FROM rep_cache;" > /dev/null sqlite3 foo.db > /dev/null 2.79s user 0.69s system 99% cpu 3.498 total % time sqlite3 foo.db "SELECT hash, revision, offset, size, expanded_size FROM rep_cache;" > /dev/null sqlite3 foo.db > /dev/null 12.62s user 0.75s system 99% cpu 13.430 total % sqlite3 -version 3.7.4 ]]] That is: adding COUNT(*) to the query makes it 3.9 times faster. Huh? How does that make sense? Should we do anything differently in our code in light of this? [ This isn't a fabricated example --- this is the query I added to rep-cache.c today ]
