|
For the query Select col1 from table1 Where col1 like ‘172.%’ The table has 133 million unique ip addresses. Col1 is
indexed. The optimizer is using a sequential scan This is the explain analyze output "Seq Scan on table1 (cost=0.00..2529284.80 rows=1
width=15) (actual time=307591.339..565251.775 rows=524288 loops=1)" " Filter: ((col1)::text ~~ '172.%'::text)" "Total runtime: 565501.873 ms" The number of affected rows (500K) is a small fraction of
the total row count. |
