Update XML Clob node - sql

Question

I have a table Transaction , in which I have a clob xclob for which ,
I want to update the "property" node's "record_start_dll_date" value to record_start_date(i.e I want to remove the _dll part )
and "record_dll_end_date" to record_end_date .
I am using oracle database . How can I modify these node values??
<?xml version ="1.0"?>
<properties>
<property name ="record_start_dll_date">
<value>1/1/2021</value>
</property>
<property name ="record_dll_end_date">
<value>21/12/2021</value>
</property>
</properties>

Answer 1

You can use an XMLQuery update, either with the specific attribute values:
xmlquery ('copy $i := $p1 modify (
(for $j in $i/properties/property[#name="record_start_dll_date"]/#name
return replace value of node $j with $p2),
(for $j in $i/properties/property[#name="record_dll_end_date"]/#name
return replace value of node $j with $p3)
) return $i'
passing xmltype(xclob) as "p1",
'record_start_date' as "p2",
'record_end_date' as "p3"
returning content)
or to strip any _dll:
xmlquery ('copy $i := $p1 modify (
for $j in $i/properties/property[contains(#name, "_dll")]/#name
return replace value of node $j with replace($j, "_dll", "")
) return $i'
passing xmltype(xclob) as "p1"
returning content)
Either way you can incorporate that into an update statement, with a matching XMLExists clause to avoid unnecessary updates:
update transaction
set xclob = xmlquery ('copy $i := $p1 modify (
for $j in $i/properties/property[contains(#name, "_dll")]/#name
return replace value of node $j with replace($j, "_dll", "")
) return $i'
passing xmltype(xclob) as "p1"
returning content).getclobval()
where xmlexists('$p1/properties/property[contains(#name, "_dll")]'
passing xmltype(xclob) as "p1")
db<>fiddle