[大数据]批量查询表的记录数语句

经常需要查询一批类似表中的记录量，通过下面的语句实现：

select 'SELECT COUNT(*) as tabnum,' || '''' || tname || '''' ||
       ' as tabname FROM ' || TNAME || ' UNION '
  from tab
 where tname like '%COMPANY%'
 ORDER BY TNAME;

执行完效果如下：

SELECT COUNT() as tabnum,‘PUBLIC_COMPANYINFO_180816’ as tabname FROM PUBLIC_COMPANYINFO_180816 UNION
SELECT COUNT() as tabnum,‘PUBLIC_COMPANYINFO_201805’ as tabname FROM PUBLIC_COMPANYINFO_201805 UNION
SELECT COUNT() as tabnum,‘PUBLIC_COMPANYINFO_201806’ as tabname FROM PUBLIC_COMPANYINFO_201806 UNION
SELECT COUNT() as tabnum,‘PUBLIC_COMPANYINFO_201807’ as tabname FROM PUBLIC_COMPANYINFO_201807 UNION
SELECT COUNT() as tabnum,‘PUBLIC_COMPANYINFO_201808’ as tabname FROM PUBLIC_COMPANYINFO_201808 UNION
SELECT COUNT() as tabnum,‘PUBLIC_COMPANYINFO_201809’ as tabname FROM PUBLIC_COMPANYINFO_201809 UNION
SELECT COUNT() as tabnum,‘PUBLIC_COMPANYINFO_201810’ as tabname FROM PUBLIC_COMPANYINFO_201810 UNION
SELECT COUNT() as tabnum,‘PUBLIC_COMPANYINFO_201811’ as tabname FROM PUBLIC_COMPANYINFO_201811 UNION
SELECT COUNT(*) as tabnum,‘PUBLIC_COMPANYINFO_201812’ as tabname FROM PUBLIC_COMPANYINFO_201812 UNION

把最后一个UNION更换成分号 ;
就可用直接执行，可以清楚看到这些表中的记录数。