BUG #15882: Select .... UNION ALL

The following bug has been logged on the website:

Bug reference:      15882
Logged by:          Vincenzo Campanella
Email address:      v.campanella47@gmail.com
PostgreSQL version: 11.4
Operating system:   windows 10 build 1903
Description:

cSelect = "select 1 as prog,sum(imp_asl) as Importo_Asl,Count(Arc_Ref.n_Rif)
as nRicette,sum(n_Pre) as nPrelievi  " +
                                    "from " + MyFunc.cSchema + "Arc_Ref " +
                                    "where data >= '" + cAnno + "-01-01' and data <= '" + cAnno +
"-01-31' and T_MPR='M' " +
                                    "union all " +
                                    "select 2 as prog,sum(imp_asl) as Importo_Asl,Count(Arc_Ref.n_Rif)
as nRicette,sum(n_Pre) as nPrelievi  " +
                                    "from " + MyFunc.cSchema + "Arc_Ref " +
                                    "where data >= '" + cAnno + "-02-01' and data <= '" + cAnno +
"-02-" + MyFunc.Ultimo_Giorno_Mese(2, Converti.ToInt32(cAnno)) + "' and
T_MPR='M' " +
                                    "union all " +
                                    "select 3 as prog,sum(imp_asl) as Importo_Asl,Count(Arc_Ref.n_Rif)
as nRicette,sum(n_Pre) as nPrelievi  " +
                                    "from " + MyFunc.cSchema + "Arc_Ref " +
                                    "where data >= '" + cAnno + "-03-01' and data <= '" + cAnno +
"-03-31' and T_MPR='M' " +
                                    "union all " +
                                    "select 4 as prog,sum(imp_asl) as Importo_Asl,Count(Arc_Ref.n_Rif)
as nRicette,sum(n_Pre) as nPrelievi  " +
                                    "from " + MyFunc.cSchema + "Arc_Ref " +
                                    "where data >= '" + cAnno + "-04-01' and data <= '" + cAnno +
"-04-30' and T_MPR='M' " +
                                    "union all " +
                                    "select 5 as prog,sum(imp_asl) as Importo_Asl,Count(Arc_Ref.n_Rif)
as nRicette,sum(n_Pre) as nPrelievi  " +
                                    "from " + MyFunc.cSchema + "Arc_Ref " +
                                    "where data >= '" + cAnno + "-05-01' and data <= '" + cAnno +
"-05-31' and T_MPR='M' " +
                                    "union all " +
                                    "select 6 as prog,sum(imp_asl) as Importo_Asl,Count(Arc_Ref.n_Rif)
as nRicette,sum(n_Pre) as nPrelievi  " +
                                    "from " + MyFunc.cSchema + "Arc_Ref " +
                                    "where data >= '" + cAnno + "-06-01' and data <= '" + cAnno +
"-06-30' and T_MPR='M' " +
                                    "union all " +
                                    "select 7 as prog,sum(imp_asl) as Importo_Asl,Count(Arc_Ref.n_Rif)
as nRicette,sum(n_Pre) as nPrelievi  " +
                                    "from " + MyFunc.cSchema + "Arc_Ref " +
                                    "where data >= '" + cAnno + "-07-01' and data <= '" + cAnno +
"-07-31' and T_MPR='M' " +
                                    "union all " +
                                    "select 8 as prog,sum(imp_asl) as Importo_Asl,Count(Arc_Ref.n_Rif)
as nRicette,sum(n_Pre) as nPrelievi  " +
                                    "from " + MyFunc.cSchema + "Arc_Ref " +
                                    "where data >= '" + cAnno + "-08-01' and data <= '" + cAnno +
"-08-31' and T_MPR='M' " +
                                    "union all " +
                                    "select 9 as prog,sum(imp_asl) as Importo_Asl,Count(Arc_Ref.n_Rif)
as nRicette,sum(n_Pre) as nPrelievi  " +
                                    "from " + MyFunc.cSchema + "Arc_Ref " +
                                    "where data >= '" + cAnno + "-09-01' and data <= '" + cAnno +
"-09-30' and T_MPR='M' " +
                                    "union all " +
                                    "select 10 as prog,sum(imp_asl) as Importo_Asl,Count(Arc_Ref.n_Rif)
as nRicette,sum(n_Pre) as nPrelievi  " +
                                    "from " + MyFunc.cSchema + "Arc_Ref " +
                                    "where data >= '" + cAnno + "-10-01' and data <= '" + cAnno +
"-10-31' and T_MPR='M' " +
                                    "union all " +
                                    "select 11 as prog,sum(imp_asl) as Importo_Asl,Count(Arc_Ref.n_Rif)
as nRicette,sum(n_Pre) as nPrelievi  " +
                                    "from " + MyFunc.cSchema + "Arc_Ref " +
                                    "where data >= '" + cAnno + "-11-01' and data <= '" + cAnno +
"-11-30' and T_MPR='M' " +
                                    "union all " +
                                    "select 12 as prog,sum(imp_asl) as Importo_Asl
,Count(Arc_Ref.n_Rif) as nRicette,sum(n_Pre) as nPrelievi " +
                                    "from " + MyFunc.cSchema + "Arc_Ref " +
                                    "where data >= '" + cAnno + "-12-01' and data <= '" + cAnno +
"-12-31' and T_MPR='M' " +
                                    "union all " +
                                    "select 13 as prog,sum(imp_asl) as Importo_Asl,Count(Arc_Ref.n_Rif)
as nRicette,sum(n_Pre) as nPrelievi  " +
                                    "from " + MyFunc.cSchema + "Arc_Ref " +
                                    "where data >= '" + cAnno + "-01-01' and data <= '" + cAnno +
"-12-31' and T_MPR='M' ";
This produces an unordered but random table.
I put the prog field and then make the ascending order on this field.
In previous versions the order was in the typed sequence.
Greetings
Enzo Campanella
(v.campanella@tin.it)