VALIDATION DU FORMAT DU N° DE TÉLÉPHONE AVEC TSQL

create TRIGGER VerifyPhone
on T_client
instead of insert,update
   as 
    begin
           declare @i smallint,@b smallint,@tel varchar(20) 
           set @tel=(select cli_tel from INSERTED)    
  
           select @b=1
           select @i=1
           while @i<=len(@tel) and @b=1
              begin
                if (ascii(substring(@tel,@i,1))<48 or ascii(substring(@tel,@i,1))>57) and (ascii(substring(@tel,@i,1))<>46)                   
                 	select @b=0
                 select @i=@i+1
              end
           if @b=0
               begin
                 ROLLBACK TRANSACTION
                 print 'Transaction annulée'
                 print 'numéro de téléphone Invalide'
               end
           else
               begin
                  if update(cli_tel)
                     delete T_client where cli_id=(select cli_id from deleted)
                  insert T_client select * from INSERTED
               end      
end