按照插件

> create extension pg_prewarm ;

缓存表

> test=# select pg_prewarm('weather','buffer' ) ;  pg_prewarm
> ------------
>           1

缓存表部分内容

test=# select pg_prewarm('weather','buffer','main',0,0) ;pg_prewarm
------------1
(1 row)

表大小只有0号页，只能缓存这么大

缓存索引

test=# \d+ weatherTable "public.weather"Column   |         Type          | Collation | Nullable | Default | Storage  | Compression | Stats target | Description
-----------+-----------------------+-----------+----------+---------+----------+-------------+--------------+-------------city      | character varying(80) |           |          |         | extended |             |              |temp_low  | integer               |           |          |         | plain    |             |              |temp_high | integer               |           |          |         | plain    |             |              |prcp      | real                  |           |          |         | plain    |             |              |date      | date                  |           |          |         | plain    |             |              |
Indexes:"idx_city" btree (city)
Access method: heaptest=# select pg_prewarm('idx_city','buffer' ) ;pg_prewarm
------------2

影响：