Im using a cursor to go over some data but I need to declare diferents sql statments according to a parameter. The problem seems to be that Im no able to use if statmets into this declaratios:
DECLARE
CURSOR c IS SELECT开发者_如何学Go * FROM TRAFICO
IF TipoConsulta = 'mes' then
BEGIN
WHERE TO_CHAR(FECHA_BUSQUEDA, 'MM-YYYY') =To_CHAR(ADD_MONTHS(SYSDATE, -1), 'MM-YYYY')
ELSE
WHERE FECHA_BUSQUEDA >= SYSDATE -7
END IF;
ORDER BY ID_TRAFICO;
begin
FOR r IN C LOOP
BEGIN
Utl_File.Put_Line(Arch, r.ID_TRAFICO );
i:=i+1;
END;
END LOOP;
END;
I just need to change the sql statment using an if.
How do I do this??
TNKS
try using a dynamic cursor REF CURSOR (i'm assuming TripoConsulta is a variable and not one of the predicates of the query):
declare
type some_cursor is ref cursor;
my_cursor some_cursor;
my_rec trafico%rowtype;
begin
if TripoConsulta = 'mes' then
open my_cursor for select * from trafico where ...;
else
open my_cursor for select * from trafico where ...;
end if;
loop
fetch my_cur into my_rec;
exit when my_cur%notfound;
Utl_File.Put_Line(my_rec.Arch, my_cur.ID_TRAFICO );
end loop;
close my_cursor;
end;
Clearly, i don't know what the variable all mean so i had to make a number of assumptions, but i'm thinking this is what you meant. I also don't guaranetee the syntax since i haven't actually tested it.
I think you might want to try the following:
SELECT * FROM TRAFICO
WHERE (TipoConsulta = 'mes'
and TO_CHAR(FECHA_BUSQUEDA, 'MM-YYYY') =To_CHAR(ADD_MONTHS(SYSDATE, -1), 'MM-YYYY'))
or (TipoConsulta <> 'mes'
and FECHA_BUSQUEDA >= SYSDATE -7)
ORDER BY ID_TRAFICO;
This uses implicit cursors, rather than splinter an explicit cursor with an OR clause or use dynamic SQL:
CASE TipoConsulta
WHEN 'mes' THEN
FOR b IN (SELECT a.*
FROM TRAFICO a
WHERE TO_CHAR(a.fecha_busqueda, 'MM-YYYY') = To_CHAR(ADD_MONTHS(SYSDATE, -1), 'MM-YYYY')
ORDER BY a.id_trafico)
UTL_FILE.PUT_LINE(Arch, b.id_trafico);
END LOOP;
ELSE
FOR d IN (SELECT c.*
FROM TRAFICO c
WHERE c.fecha_busqueda >= SYSDATE - 7
ORDER BY c.id_trafico)
UTL_FILE.PUT_LINE(Arch, d.id_trafico);
END LOOP;
END CASE;
This also uses a PLSQL CASE expression, rather than the ANSI CASE expression -- you can tell by the use of END CASE
, when ANSI CASE just uses END
.
It doesn't appear that you posted the entire query - I don't know where arch
is coming from, nor the need for the incrementing variable i
... Or why you've got SELECT * FROM TRAFICO
but only using the id_trafico
column...
精彩评论