查询MYSQL、Oracle和达梦数据库表数据量

MYSQL

SELECT table_name, table_rows 
FROM information_schema.tables 
WHERE table_schema = 'your_database_name' 
ORDER BY table_rows DESC;

Oracle

SELECT table_name, to_number(extractvalue(xmltype(
    dbms_xmlgen.getxml('select count(*) c from '||table_name))
  ,'/ROWSET/ROW/C')) AS row_count
FROM user_tables
ORDER BY row_count DESC ;

达梦

SELECT B.OWNER,B.TABLE_NAME,TABLE_ROWCOUNT(B.OWNER,B.TABLE_NAME) "TABLE_ROWS"
FROM (SELECT A.OWNER,A.TABLE_NAME FROM ALL_TABLES A WHERE A.TABLE_NAME NOT LIKE 'CTI%' AND A.TABLE_NAME NOT LIKE 'SREF_CON_TAB%' AND A.TABLE_NAME NOT LIKE 'BM%'
) B where B.OWNER='schema_name'
ORDER BY 3 DESC,1,2;

 

表中存了多少数据

select table_schema as 数据库,
       table_name AS 表名,
       truncate(data_length/1024/1024,2) as 数据容量（MB）,
       truncate(index_length/1024/1024,2) as 索引容量（MB）
from
    information_schema.TABLES
where
    TABLE_SCHEMA='数据库名'
  and TABLE_NAME='数据库中的表名'
order by
    data_length desc,
    index_length desc;