postgresql study note
PostgreSQL的外键深入使用 - kenyon的个人页面 - 开源中国社区pgdump -h ip -Uusername dbname >sqlfilename.sql
pgdump -Fc -h ip -Uusername dbname >*.dump
create newdbname
pg_restore -d newdbname *.dump
--创建 schema
\c dbname 切换目标数据库
create schema schemaName owner lv;
drop schema schemaName;
alter schema schemaName owner useName;
\dn 查看创建结果
ssh ip
su passwd postgres
su - postgres
地理位置：
CREATE TABLE user_loc(
ud char(6),
loc1 point
);
INSERT INTO user_loc VALUES ('a', '(1, 1.0)');
INSERT INTO user_loc VALUES ('b', '(2, 2.0)');
select lseg '((0, 1),(1, 0))' <-> lseg '((0, 2),(2, 0))';
select point '(1,1)' <-> point '(2,2)' from user_loc; -- ok
select loc1 <-> loc2 from user_loc; -- ok
select ud from user_loc where a (lseg (a.loc1 <->(select b.loc1 from user_loc b where b. )))= 1.4142135623731;
select bb.ud from user_loc aa, user_loc bb where (lseg (aa.loc1 <-> bb.loc1)) = 1.4142135623731;
页:
[1]