Applied cleanly for me. Here are my performance test results: count --------- 3000000 (1 row)
Time: 3167.836 ms (00:03.168) count ---------- 10100000 (1 row) Time: 6074.369 ms (00:06.074) count ------- 10001 (1 row) Time: 8.159 ms The performance improves substantially in case 2 as advertised: count --------- 3000000 (1 row) Time: 3387.612 ms (00:03.388) count ---------- 10100000 (1 row) Time: 43794.224 ms (00:43.794) count ------- 10001 (1 row) Time: 1436.587 ms (00:01.437) I'll do some more testing to determine how this behaves in the presence of multibyte characters in UTF-8.
