rafsun42 commented on code in PR #1013:
URL: https://github.com/apache/age/pull/1013#discussion_r1347669242
##########
src/backend/utils/adt/agtype.c:
##########
@@ -4972,6 +4972,54 @@ Datum age_last(PG_FUNCTION_ARGS)
PG_RETURN_POINTER(agtype_value_to_agtype(agtv_result));
}
+PG_FUNCTION_INFO_V1(age_tail);
+/*
+ * Returns a list containing all the elements, excluding the first one, from
a list.
+ */
+Datum age_tail(PG_FUNCTION_ARGS)
+{
+ agtype *agt_arg = NULL;
+ agtype_in_state agis_result;
+ int count;
+ int i;
+
+ /* check for null */
+ if (PG_ARGISNULL(0))
+ PG_RETURN_NULL();
+
+ agt_arg = AG_GET_ARG_AGTYPE_P(0);
+ /* check for an array */
+ if (!AGT_ROOT_IS_ARRAY(agt_arg) || AGT_ROOT_IS_SCALAR(agt_arg))
+ ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("tail() argument must resolve to a list or
null")));
+
+ count = AGT_ROOT_COUNT(agt_arg);
+
+ /* if we have an empty list or only one element in the list, return null */
+ if (count <= 1)
+ PG_RETURN_NULL();
+
+ /* clear the result structure */
+ MemSet(&agis_result, 0, sizeof(agtype_in_state));
+
+ /* push the beginning of the array */
+ agis_result.res = push_agtype_value(&agis_result.parse_state,
+ WAGT_BEGIN_ARRAY, NULL);
+
+ /* iterate through the list beginning with the second item */
+ for (i = 1; i < count; i++)
+ {
+ agis_result.res = push_agtype_value(&agis_result.parse_state,
WAGT_ELEM,
+
get_ith_agtype_value_from_container(&agt_arg->root, i));
+ }
+
+ /* push the end of the array */
+ agis_result.res = push_agtype_value(&agis_result.parse_state,
+ WAGT_END_ARRAY, NULL);
+
+ PG_RETURN_POINTER(agtype_value_to_agtype(agis_result.res));
Review Comment:
Should we free the agtype_value from the memory (i.e. using
`pfree_agtype_value`), since we are not returning it?
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
