Passing parameters in order by clause of cursor

Question

Hi friends,
I am facing a strange problem
I have a cursor with a order by clause.
OPEN cursor_nomrpt FOR
SELECT DISTINCT
CAST(plano.desc3 AS VARCHAR2(50)) category
,plano.name plan_name
,nvl(CAST(plano.desc6 AS VARCHAR2(50)),'not applicable') pcrr
,nvl(trunc(plano.value18,2),0) nominal_slm
,nvl(trunc(plano.value19,2),0) blm
,plano.dbdateeffectivefrom date_live
plano.dbkey pog_id
,case when plano.value47 < 0 THEN 0 when plano.value47 IS NULL THEN 0 ELSE plano.value47 END AS parent_id
FROM
dplapro1.ix_spc_planogram plano
INNER JOIN dplapro1.ix_spc_performance perf ON plano.dbkey = perf.dbparentplanogramkey
INNER JOIN dplapro1.ix_spc_product product ON perf.dbparentproductkey = product.dbkey
INNER JOIN dplapro1.ix_spc_product_key prodkey ON product.dbkey2 = prodkey.dbkey
AND prodkey.keylevel = 2
WHERE
plano.value50 = 0
AND plano.dbkey4 = p_subcatkey
ORDER BY ltrim(rtrim(p_orderby)) ASC;
p_orderby is the parameter being passed. But the output is not sorted. But when I run the cursor by hardcoding the parameter value it works fine...
Need your help on this

Answer 1

Hi,
When you use a local variable in a cursor, it's as if you had hard-coded a literal in its place, so you can't use a variable for a column name.
If you know all the possible values of p_orderby, you can do something like this:
ORDER BY  TRIM ( CASE  p_orderby
               WHEN  'DESC'     THEN  plano.desc
               WHEN  'VALUE'     THEN  plano.value
           END
            ) ASC;If you don't know all the possible values, you could use dynamic SQL.
By the way,
TRIM (x)returns the same results as
LTRIM ( RTRIM (x))