clickhouse查看数据库和表的容量信息

标签：压缩率 数据库 bytes 和表 formatReadableSize uncompressed data sum clickhouse

      在mysql中information_schema这个数据库中保存了mysql服务器所有数据库的信息，那在clickhouse如何查询库表信息呢？

 可以通过system.parts查看clickhouse数据库和表的容量大小、行数、压缩率以及分区信息。
     详见正面实操，只是其中一例，大家可以举一返三。

 

1、查看数据表容量、行数、压缩率

SELECT     table AS `表名`,     sum(rows) AS `总行数`,     formatReadableSize(sum(data_uncompressed_bytes)) AS `原始大小`,     formatReadableSize(sum(data_compressed_bytes)) AS `压缩大小`,     round((sum(data_compressed_bytes) / sum(data_uncompressed_bytes)) * 100, 0) AS `压缩率` FROM system.parts WHERE (database IN ('mydatabasename')) GROUP BY table  

2、查看数据表分区信息

SELECT  table AS `表名`,     partition AS `分区`,     sum(rows) AS `总行数`,     formatReadableSize(sum(data_uncompressed_bytes)) AS `原始大小`,     formatReadableSize(sum(data_compressed_bytes)) AS `压缩大小`,     round((sum(data_compressed_bytes) / sum(data_uncompressed_bytes)) * 100, 0) AS `压缩率` FROM system.parts WHERE (database IN ('mydatabasename')) GROUP BY table,partition ORDER BY partition ASC
 

3、查看数据库容量、行数、压缩率

SELECT     sum(rows) AS `总行数`,     formatReadableSize(sum(data_uncompressed_bytes)) AS `原始大小`,     formatReadableSize(sum(data_compressed_bytes)) AS `压缩大小`,     round((sum(data_compressed_bytes) / sum(data_uncompressed_bytes)) * 100, 0) AS `压缩率` FROM system.parts WHERE (database IN ('mydatabasename'))

标签：压缩率,数据库,bytes,和表,formatReadableSize,uncompressed,data,sum,clickhouse
From： https://www.cnblogs.com/xuzhujack/p/18028920