greenplum(gp)的常用命令

连接gp命令:  
psql -d 库名 -h ip地址 -p 端口号 -U 用户名;
gp 添加分区: 
alter table 表名 add partition d20190611 values('20190611') ;
gp 添加字段:
alter table 表名 add column update_flag varchar(255);
gp 重命名:
alter table 表名 rename column old_column_name to new_column_name;  
gp 删除字段:
ALTER TABLE 表名 DROP COLUMN rt_gather_price_remark;
gp 修改字段的类型:
alter table 表名 alter column rt_gather_price_remark varchar(200) text; 
gp 删除表:
drop table if exists 表名;
gp 删除分区:
alter table 表名 DROP partition d20190729;
gp 清空分区数据:
alter table 表名 truncate partition d20191010;
gp 删除进程:
select pg_cancel_backend(407367);
gp 查看表结构:
SELECT a.attnum,a.attname AS field,t.typname AS type,a.attlen AS length,a 
.atttypmod AS lengthvar,a.attnotnull AS notnull from pg_class c,pg_attribute a,pg_type t where 
c.relname='表名' and a.attnum>0 and a.attrelid=c.oid and a.atttypid=t.oid order by attnum ;