postgres†

select†

select * from [table] where [colomn] is null;
select * from [table] where [colomn] is not null;
select * from [table] where [colomn] like '%hoge%';
select * from [table] where [colomn] not like '%hoge%';

重複削除†

delete from 【TABLE】 where 【ID】 in 
  (select 【ID】 
   from   【TABLE】 S1 
   where  【ID】< (select MAX(【ID】) from 【table】 as S2 where 
     S1.key1=S2.key1 and S1.key2=S2.key2 ..... ) ) ;

psql 編†

psql†

psql [-h 【hostname】] -d 【dbname】

backup†

pg_dump 【dbname】 > dbname.dump

復活†

psql -d 【dbname】 -f dbname.dump

重複検索†

select min(id) from item group by time having count(*) > 1