方式一：（表大时较慢）
select count(*) as rows from table_name方式二：(数据库里本身存的信息，速度较快）
SELECT a.name, b.rows,b.indid FROM sysobjects AS a INNER JOIN sysindexes AS b ON a.id = b.id WHERE b.indid in (0,1) and a.name = 'table_name' ORDER BY a.name,b.rows DESC如查询表DM_FACT_SALES的数据行数
SELECT a.name, b.rows,b.indid FROM sysobjects AS a INNER JOIN sysindexes AS b ON a.id = b.id WHERE b.indid in (0,1) and a.name = 'DM_FACT_SALES' ORDER BY a.name,b.rows DESC