Subquery within MERGE?

Question

Hello,
I'm having a bit of difficulty getting a MERGE command to work with a subquery as part of the imported data. Thoughts?
-- Clean up from prior run, if there was one
DROP TABLE PARENT CASCADE CONSTRAINTS;
DROP TABLE CHILD CASCADE CONSTRAINTS;
DROP TABLE INPUT CASCADE CONSTRAINTS;
DROP SEQUENCE ENTERPRISE_SEQ;
--create objects for test
CREATE TABLE PARENT(
PARENT_ENTERPRISE_ID NUMBER(4, 0) NOT NULL,
PARENT_SOURCE_NAME VARCHAR2(20) NOT NULL,
PARENT_SOURCE_ID VARCHAR2(20) NOT NULL,
PARENT_COMMENT VARCHAR2(25) NOT NULL,
CONSTRAINT PARENT_PK PRIMARY KEY (PARENT_ENTERPRISE_ID),
CONSTRAINT PARENT_AK UNIQUE (PARENT_SOURCE_NAME, PARENT_SOURCE_ID)
CREATE SEQUENCE ENTERPRISE_SEQ;
CREATE TABLE CHILD(
PARENT_ENTERPRISE_ID NUMBER(4, 0) NOT NULL,
CHILD_ENTERPRISE_ID NUMBER(4, 0) NOT NULL,
CHILD_SOURCE_NAME VARCHAR2(20) NOT NULL,
CHILD_SOURCE_ID VARCHAR2(20) NOT NULL,
CHILD_COMMENT VARCHAR2(25) NOT NULL,
CONSTRAINT CHILD_PK PRIMARY KEY (CHILD_ENTERPRISE_ID),
CONSTRAINT CHILD_AK UNIQUE (CHILD_SOURCE_NAME, CHILD_SOURCE_ID)
ALTER TABLE CHILD
ADD CONSTRAINT CHILD_FK_PARENT
FOREIGN KEY (PARENT_ENTERPRISE_ID)
REFERENCES PARENT(PARENT_ENTERPRISE_ID)
CREATE TABLE INPUT(
INPUT_SOURCE_NAME VARCHAR2(10) NOT NULL,
INPUT_SOURCE_ID VARCHAR2(20) NOT NULL,
INPUT_RECORD_LEVEL VARCHAR2(10) NOT NULL,
INPUT_COMMENT VARCHAR2(25) NOT NULL,
INPUT_PARENT_RECORD_ID VARCHAR2(20) NULL,
CONSTRAINT INPUT_PK PRIMARY KEY (INPUT_SOURCE_NAME, INPUT_SOURCE_ID)
-- insert records into the table simulating external input
-- note that the input table has two levels of records: Parent and Child
insert into INPUT values ('Source A', '123', 'Parent', 'Input rec 1', null);
insert into INPUT values ('Source A', '234', 'Parent', 'Input rec 2', null);
insert into INPUT values ('Source A', '345', 'Child', 'Input rec 3', '123');
insert into INPUT values ('Source A', '456', 'Child', 'Input rec 4', '123');
-- Merge into Parent table
-- This works just fine
merge into PARENT P
using (select INPUT_SOURCE_NAME,
INPUT_SOURCE_ID,
INPUT_COMMENT
from INPUT
where INPUT_RECORD_LEVEL = 'Parent'
) I
on (I.INPUT_SOURCE_NAME = PARENT_SOURCE_NAME and
I.INPUT_SOURCE_ID = PARENT_SOURCE_ID
when matched then
update set P.PARENT_COMMENT = I.INPUT_COMMENT
when not matched then
insert (P.PARENT_ENTERPRISE_ID,
P.PARENT_SOURCE_NAME,
P.PARENT_SOURCE_ID,
P.PARENT_COMMENT
values
(ENTERPRISE_SEQ.NEXTVAL,
I.INPUT_SOURCE_NAME,
I.INPUT_SOURCE_ID,
I.INPUT_COMMENT
-- Merge into Child table
-- This fails
merge into CHILD C
using (select INPUT_SOURCE_NAME,
INPUT_SOURCE_ID,
INPUT_COMMENT
from INPUT
where INPUT_RECORD_LEVEL = 'Child'
) I
on (I.INPUT_SOURCE_NAME = C.CHILD_SOURCE_NAME
and
I.INPUT_SOURCE_ID = C.CHILD_SOURCE_ID
when matched then
update set C.CHILD_COMMENT = I.INPUT_COMMENT
when not matched then
insert (C.PARENT_ENTERPRISE_ID,
C.CHILD_ENTERPRISE_ID,
C.CHILD_SOURCE_NAME,
C.CHILD_SOURCE_ID,
C.CHILD_COMMENT
values
((select PARENT_ENTERPRISE_ID
from PARENT
where PARENT_SOURCE_NAME = I.INPUT_SOURCE_NAME
and PARENT_SOURCE_ID = I.INPUT_SOURCE_ID
ENTERPRISE_SEQ.NEXTVAL,
I.INPUT_SOURCE_NAME,
I.INPUT_SOURCE_ID,
I.INPUT_COMMENT
select * from PARENT;
select * from CHILD;

Answer 1

ME_XE?merge into child c
  2  using
  3  (
  4     select
  5             i.input_source_name,
  6             i.input_source_id,
  7             i.input_comment,
  8             p.parent_enterprise_id
  9     from
10             input   i,
11             parent  p
12     where i.input_record_level              = 'Child'
13     and   i.input_source_name               = p.parent_source_name
14     and   i.input_parent_record_id          = p.parent_source_id
15  ) i
16  on
17  (
18             i.input_source_name = c.child_source_name
19     and     i.input_source_id   = c.child_source_id
20  )
21  when matched then
22     update set c.child_comment = i.input_comment
23  when not matched then
24  insert
25  (
26     c.parent_enterprise_id,
27     c.child_enterprise_id,
28     c.child_source_name,
29     c.child_source_id,
30     c.child_comment
31  )
32  values
33  (
34     i.parent_enterprise_id,
35     enterprise_seq.nextval,
36     i.input_source_name,
37     i.input_source_id,
38     i.input_comment
39  );
2 rows merged.
Elapsed: 00:00:00.01
ME_XE?
ME_XE?
ME_XE?select * from parent;
PARENT_ENTERPRISE_ID PARENT_SOURCE_NAME                                           PARENT_SOURCE_ID                                             PARENT_COMMENT
                   1 Source A                                                     123                                                          Input rec 1
                   2 Source A                                                     234                                                          Input rec 2
2 rows selected.
Elapsed: 00:00:00.00
ME_XE?select * from child;
PARENT_ENTERPRISE_ID CHILD_ENTERPRISE_ID CHILD_SOURCE_NAME                                            CHILD_SOURCE_ID                                              CHILD_COMMENT
                   1                   3 Source A                                                     345                                                          Input rec 3
                   1                   4 Source A                                                     456                                                          Input rec 4
2 rows selected.
Elapsed: 00:00:00.01
ME_XE?