DWS 查看表占用空间大小

在 DWS 中，可以使用以下 SQL 语句查看表占用的空间大小：

SELECT
    schemaname || '.' || tablename AS TableFullName,
    pg_size_pretty(table_size) AS TableSize,
    pg_size_pretty(total_size - table_size) AS IndexSize,
    pg_size_pretty(total_size) AS TotalSize
FROM (
    SELECT 
        pg_tablespace_size(spcname) AS tablespace_size,
        pg_total_relation_size(relid) AS total_size,
        pg_indexes_size(relid) AS index_size,
        pg_total_relation_size(relid) - pg_indexes_size(relid) AS table_size,
        schemaname,
        tablename
    FROM pg_catalog.pg_statio_user_tables
    JOIN pg_catalog.pg_tables ON relname = tablename
    JOIN pg_catalog.pg_namespace ON relnamespace = pg_namespace.oid
    JOIN pg_catalog.pg_tablespace ON spcname = pg_tablespace.spcname
) AS table_sizes
ORDER BY total_size DESC;

这条 SQL 语句会返回一个结果集，其中包含每个表的全名、表占用空间大小、索引占用空间大小和总空间大小（以易读的格式显示）。你可以根据需要修改 SQL 语句中的过滤条件和排序方式。