You can pass the date time value like sting (not a date format) using below format
tib:format-dateTime(‘yyyy-MM-dd HH:mm:ss’, current-dateTime())
and you query also like below
update <

I tried the function tib:format-dateTime(‘MM/DD/YYYY hh:mm:hh’, current-date())
and got the below error
com.tibco.xml.data.primitive.XmlAtomicValueParseException: Invalid value for datatype xs:dateTime: “xdt:untypedAtomic(‘2014-01-15+05:30’)”.
Invalid value for datatype xs:dateTime: “xdt:untypedAtomic(‘2014-01-15+05:30’)”.