Select statement will only accept datepicker data if filled in

Question

In my report region source i have the following. it works but some times the user want to have all the dates from :P20_XXD and :P20_DD2
But the report gives you nothing if don't fill in the two date pickers.
select
incident_id,
incident_type,
status,
ccb_identifier,
last_name,
dbms_lob.substr("PROBLEM_TITLE",4000,1) "PROBLEM_TITLE",
dbms_lob.substr("PROBLEM_DESCRIPTION",4000,1) "PROBLEM_DESCRIPTION",
create_datex ,
related_item,
dbms_lob.substr("RESOLUTION_DIARY",4000,1) "RESOLUTION_DIARY"
from "KEYHD"
where "INCIDENT_TYPE" like :P20_LIST_INCIDENT_TYPE
and (CREATE_DATEX >= TO_DATE(:P20_XDD,'DD/MM/YYYY')
and CREATE_DATEX <= TO_DATE(:P20_DD2,'DD/MM/YYYY'))

Answer 1

If values from the date pickers are not supplied then the resulting null value(s) don't satisfy the date comparison predicate. Null values need to be replaced by suitable defaults, e.g. by using the nvl function:
select
incident_id,
incident_type,
status,
ccb_identifier,
last_name,
dbms_lob.substr("PROBLEM_TITLE",4000,1) "PROBLEM_TITLE",
dbms_lob.substr("PROBLEM_DESCRIPTION",4000,1) "PROBLEM_DESCRIPTION",
create_datex ,
related_item,
dbms_lob.substr("RESOLUTION_DIARY",4000,1) "RESOLUTION_DIARY"
from "KEYHD"
where "INCIDENT_TYPE" like :P20_LIST_INCIDENT_TYPE
and (CREATE_DATEX >= nvl(TO_DATE(:P20_XDD,'DD/MM/YYYY'), date '-4712-01-01')
and CREATE_DATEX <= nvl(TO_DATE(:P20_DD2,'DD/MM/YYYY'), date '9999-12-31'))(Always post code wrapped in \&hellip;\ tags to preserve formatting).