Kevin Grittner <kgri...@ymail.com> wrote: > test=# explain analyze select word from words order by word <-> 'caterpiler' > limit 10; > Foreign Scan on words > Total runtime: 218.966 ms
> test=# explain analyze select word from wrd order by word <-> 'caterpiler' > limit 10; > Index Scan using wrd_trgm on wrd > Total runtime: 25.884 ms I forgot to put the initial check for a valid word, where the difference is much larger: test=# explain analyze select count(*) from words where word = 'caterpiler'; QUERY PLAN ---------------------------------------------------------------------------------------------------------------- Aggregate (cost=4125.19..4125.20 rows=1 width=0) (actual time=26.013..26.014 rows=1 loops=1) -> Foreign Scan on words (cost=0.00..4124.70 rows=196 width=0) (actual time=26.011..26.011 rows=0 loops=1) Filter: (word = 'caterpiler'::text) Rows Removed by Filter: 99171 Foreign File: /etc/dictionaries-common/words Foreign File Size: 938848 Total runtime: 26.081 ms (7 rows) test=# explain analyze select count(*) from wrd where word = 'caterpiler'; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------- Aggregate (cost=4.44..4.45 rows=1 width=0) (actual time=0.074..0.074 rows=1 loops=1) -> Index Only Scan using wrd_word on wrd (cost=0.42..4.44 rows=1 width=0) (actual time=0.071..0.071 rows=0 loops=1) Index Cond: (word = 'caterpiler'::text) Heap Fetches: 0 Total runtime: 0.119 ms (5 rows) The question remains the same, though ... document this usage? -- Kevin Grittner EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
