文件名称:同步语句-信号处理_python科学计算
文件大小:1.92MB
文件格式:PDF
更新时间:2024-07-18 21:04:54
greenplum mpp
2.1 查看原始表的大小行数与结构 原始数据的大小 select pg_size_pretty(pg_relation_size('dim.test1')); -- 43 GB 原始数据的行数 select count(*) from dim.test1; -- 182,683,056 原始数据的表结构 stagging=# \d dim.test1; Table "dim.test1" Column | Type | Modifiers -----------+------------------------+----------- zspid | character varying(500) | encode_v1 | character varying(500) | encode_v2 | character varying(500) | Distributed by: (zspid) 2.2 同步语句 create table ods.test1 with (appendonly = true, compresstype = zlib, compresslevel = 5 ,orientation=column, checksum = false,blocksize = 2097152) as select zspid,encode_v1,encode_v2 from dim.test1 Distributed by (zspid);