WHERE (CASE LENGTH('${p_saledept}') WHEN 6 THEN Da.BRANCHCODE when 9 then da.dept_parent_deptno END) = '${p_saledept}'
CASE WHEN LENGTH('${p_saledept}') = 0 THEN 1 = 1 WHEN LENGTH('${p_saledept}') = 6 THEN Da.BRANCHCODE = '${p_saledept}' WHEN LENGTH('${p_saledept}') = 9 THEN a.dept_parent_deptno = '${p_saledept}' ELSE 1=2 END
case isnull('${p_saledept}') when 6 then ...
WHERE (CASE '${len(p_saledept)}' WHEN 6 THEN Da.BRANCHCODE when 9 then da.dept_parent_deptno when 0 then '${p_saledept}' END)='${p_saledept}'