Is this expected? (Index scanning)
От | Mitch Vincent |
---|---|
Тема | Is this expected? (Index scanning) |
Дата | |
Msg-id | 001b01c0d69c$170b9090$1251000a@windows обсуждение исходный текст |
Ответы |
Re: Is this expected? (Index scanning)
|
Список | pgsql-general |
Indexes on both void and lower(cust_name) here.. I get -> EXPLAIN select * from invoice_master WHERE lower(cust_name) like 'mitch' AND void = 'f' order by created LIMIT 100; NOTICE: QUERY PLAN: Limit (cost=2241.98..2241.98 rows=100 width=319) -> Sort (cost=2241.98..2241.98 rows=604 width=319) -> Index Scan using invoice_cust_name on invoice_master (cost=0.00..2214.09 rows=604 width=319) The above query matches zero rows. EXPLAIN SELECT * FROM invoice_master WHERE lower(cust_name) like '%mitch' AND void = 'f' ORDER BY created LIMIT 100; NOTICE: QUERY PLAN: Limit (cost=4310.65..4310.65 rows=1 width=319) -> Sort (cost=4310.65..4310.65 rows=1 width=319) -> Seq Scan on invoice_master (cost=0.00..4310.64 rows=1 width=319) The above query matches zero rows. EXPLAIN SELECT * FROM invoice_master WHERE lower(cust_name) like 'mitch%' AND void = 'f' ORDER BY created LIMIT 100; NOTICE: QUERY PLAN: Limit (cost=2241.98..2241.98 rows=100 width=319) -> Sort (cost=2241.98..2241.98 rows=604 width=319) -> Index Scan using invoice_cust_name on invoice_master (cost=0.00..2214.09 rows=604 width=319) The above query matches 53 rows.. PostgreSQL 7.1.1, FreeBSD 4.2, 73408 records in the invoice_master table and it's all freshly vacuum analyze 'd... I'm just wondering if I'm doing something extremely silly here.. Thanks!! -Mitch
В списке pgsql-general по дате отправления: