PostgreSQL stream repication can implement between FreeBSD and CentOS

postgres@digoal:~ % pg_ctl promote
server promoting
postgres@digoal:~ % psql
psql (9.3.4)
Type "help" for help.

postgres=> create table test(id int primary key, info text, crt_time timestamp);
CREATE TABLE
postgres=> create or replace function f(v_id int) returns void as $$
postgres$> declare
postgres$> begin
postgres$>   update test set info=md5(now()::text),crt_time=now() where id=v_id;
postgres$>   if not found then
postgres$>     insert into test values (v_id, md5(now()::text), now());
postgres$>   end if;
postgres$>   exception when others then
postgres$>     return;
postgres$> end;
postgres$> $$ language plpgsql strict;
sCREATE FUNCTION
postgres=> select f(1);
 f 
---
 
(1 row)

postgres=> select * from test;
 id |               info               |          crt_time          
----+----------------------------------+----------------------------
  1 | 9de5370fe00c7ed52b48080e2fb3efc9 | 2014-06-27 19:07:14.725201
(1 row)

postgres=> select f(1);
 f 
---
 
(1 row)

postgres=> select * from test;
 id |               info               |          crt_time          
----+----------------------------------+----------------------------
  1 | f91841b8d4a52cb4ce82e835aa161283 | 2014-06-27 19:07:20.969022
(1 row)

postgres@digoal:~ % cd
postgres@digoal:~ % vi test.sql
\setrandom v_id 1 50000000
select f(:v_id);

postgres@digoal:~ % pgbench -M prepared -n -r -f ./test.sql -c 16 -j 4 -T 30
transaction type: Custom query
scaling factor: 1
query mode: prepared
number of clients: 16
number of threads: 4
duration: 30 s
number of transactions actually processed: 1512165
tps = 50368.843235 (including connections establishing)
tps = 50416.031069 (excluding connections establishing)
statement latencies in milliseconds:
        0.001875        \setrandom v_id 1 50000000
        0.313934        select f(:v_id);

        

          
        
        
        

          

          AI 代码解读