>;with cte as (select Client.*, COALESCE(Company.NoProvince, 84) as NoProvince 
>from Client LEFT JOIN Company ON Client.NoCompany = Company.Numero and Company.NoCountry = 1
>WHERE Client.FirstAcceptDate>'1899-12-30 00:00:00.000' AND
>    Client.QueryDate>'1899-12-30 00:00:00.000' AND
>    Client.QueryDate>=Client.FirstAcceptDate AND
>    Client.NoCompany>0
>UNION ALL
>select Client.*, COALESCE(Research.NoProvince, 84) as NoProvince 
>from Client LEFT JOIN Research ON Client.NoReseach = Research.Numero and Research.NoCountry = 1
>WHERE Client.FirstAcceptDate>'1899-12-30 00:00:00.000' AND
>    Client.QueryDate>'1899-12-30 00:00:00.000' AND
>    Client.QueryDate>=Client.FirstAcceptDate AND
>    Client.NoResearch>0)
>
>select * from cte