firebird, native function to format date

Firebird does not have a function ready to format date. I believe you can create a procedure that returns a formatted date. There is a SELECT to return the date in dd / MM / yyyy format.

SELECT CAST(EXTRACT(DAY FROM Campo) || '/' || EXTRACT(MONTH FROM
Campo) || '/' || EXTRACT(YEAR FROM Campo) AS VARCHAR) AS DIA_MES_ANO FROM Tabela;

Procedure that passes an integer value that returns the date according to a country, in this case Brazil equals 1 and US equals 2 for the variable res declared as return.

create procedure formatdate(locale int) returns (res date)
begin

    // Formato brasileiro
    IF (locale = 1) THEN BEGIN
       SELECT CAST(EXTRACT(DAY FROM Campo) || '/' || EXTRACT(MONTH FROM
        Campo) || '/' || EXTRACT(YEAR FROM Campo) AS VARCHAR) AS DIA_MES_ANO FROM Tabela INTO res;
    END;

    // Formato americano
    IF (locale = 2) THEN BEGIN
       SELECT CAST(EXTRACT(MONTH FROM Campo) || '/' || EXTRACT(DAY FROM
        Campo) || '/' || EXTRACT(YEAR FROM Campo) AS VARCHAR) AS DIA_MES_ANO FROM Tabela INTO res;
    END;

end;

I use a proc for this.

 create or alter procedure SP_FORMATA_DATA (
        DATA DATA)
    returns (
        RESULTADO varchar(10))
    as
    BEGIN
      -- Sem data?
      IF(DATA IS NULL)THEN
        -- Sem resultado tambem.
        RESULTADO = NULL;
      ELSE
        -- Converte a data p/ texto no formato brasileiro.
        RESULTADO = (LPAD(EXTRACT(DAY FROM DATA), 2, '0') || '/' ||
                     LPAD(EXTRACT(MONTH FROM DATA), 2, '0') || '/' ||
                     LPAD(EXTRACT(YEAR FROM DATA), 4, '0'));
      -- Retorna o resultado.
      SUSPEND;
    END

And to call the proc:

SELECT * FROM SP_FORMATA_DATA('2014.04.14')

Here I use Visual Studio 2015 and I use it in query routines by dates

where (SUBSTRING (DST001.DATA_FAT FROM 7 FOR 4) || SUBSTRING (DST001.DATA_FAT FROM 4 FOR 2) || SUBSTRING (DST001.DATA_FAT FROM 1 FOR 2)) BETWEEN '' & ANOMESDIA_INI & And '"& ANOMESDIA_FIM &" "" &

Try this  In my DB I store the dates as varchar (10) - DD / MM / YYYY I get the dates of a datetimepicker and strings the strings anomesdia. ANOMESDIA_INI as string="20170919" ANOMESDIA_FIM as string="20170922"