select b.empl_email, b.empl_no, b.empl_nm, "메일주소에공백이없어야하고"
   from #M5_email_chk b
  where charindex(' ',ltrim(rtrim(b.empl_email))) > 0
   --메일주소에공백이없어야하고

 union
 select b.empl_email, b.empl_no, b.empl_nm, "메일주소가@로시작하지말아야하고"
   from #M5_email_chk b
  where left(ltrim(empl_email),1) = '@'
 --메일주소가@로시작하지말아야하고

union
 select b.empl_email, b.empl_no, b.empl_nm, "메일주소가.로끝나지말아야하고"
   from #M5_email_chk b
  where right(rtrim(b.empl_email),1) = '.'
 --메일주소가.로끝나지말아야하고

union
 select b.empl_email, b.empl_no, b.empl_nm, "@보다.이뒤에있어야하고"
   from #M5_email_chk b
  where (charindex('.',ltrim(rtrim(b.empl_email))) - charindex('@',b.empl_email)) <= 1
 --@보다.이뒤에있어야하고

union
 select b.empl_email, b.empl_no, b.empl_nm , "메일주소전체길이에서@를뺀길이가1이어야 하고"
   from #M5_email_chk b
  where datalength(ltrim(rtrim(b.empl_email))) - datalength(str_replace(ltrim(rtrim(b.empl_email)),'@',space(-1))) <> 1
 --메일주소전체길이에서@를뺀길이가1이어야 하고

union
 select b.empl_email, b.empl_no, b.empl_nm, ".앞에3자이상이어야하며"
   from #M5_email_chk b
  where charindex('.',convert(varchar(200),(ltrim(rtrim(b.empl_email))))) < 3
 --.앞에3자이상이어야하며

union
 select b.empl_email, b.empl_no, b.empl_nm, "@가메일주소맨앞이아니고.인연속이지 않아야한다"
   from #M5_email_chk b
  where charindex('.@',b.empl_email) > 0
 --@가메일주소맨앞이아니고.인연속이지 않아야한다

union
 select b.empl_email, b.empl_no, b.empl_nm, "@가메일주소맨앞이아니고.인연속이지 않아야한다 "
   from #M5_email_chk b
  where charindex('..',b.empl_email) > 0
 --@가메일주소맨앞이아니고.인연속이지 않아야한다