Merge where definition exists - sql

Question

I have 3 tables I'm working with here. ATTRIBUTE_MAP, GROUP_DEFINITIONS, and GROUP_MAP.
ATTRIBUTE_MAP contains the CUST_ID and the associated ATTRIBUTE_ID.
GROUP_DEFINITIONS defines a group. Its columns are GROUP_ID, ATTRIBUTE_1, VALUE_1, ATTRIBUTE_2, VALUE_2, ATTRIBUTE_3, VALUE_3 A group consists of 1 to 3 attributes with values. For example, an attribute could be 'State' with its value being 'New York'. Values can also be null for boolean values like 'Owns Car'.
GROUP_MAP simply maps the CUST_ID to a GROUP_ID.
Now, I'm trying to write a script that will look at the ATTRIBUTE_MAP and see if a customer falls into one of the defined groups in GROUP_DEFINITIONS. If he (the customer) does, then insert/update a row into GROUP_MAP with the CUST_ID and GROUP_ID. The part I'm having trouble with, is matching the attribute values.
Here is what I have so far:
merge GROUP_MAP gm using
( select am.CUST_ID
,am.ATTRIBUTE_ID
,am.START_DATE
,gd.GROUP_ID
,gd.ATTRIBUTE_1
,gd.VALUE_1
,gd.ATTRIBUTE_2
,gd.VALUE_2
,gd.ATTRIBUTE_3
,gd.VALUE_3
from ATTRIBUTE_MAP am, GROUP_DEFINITIONS gd ) src
on gm.GROUP_ID=src.GROUP_ID
AND gm.CUST_ID=src.CUST_ID
when not matched then -- create association in GROUP_MAP
insert (CUST_ID, GROUP_ID, FROM_DATE)
values (src.CUST_ID, src.GROUP_ID, src.START_DATE);
Am I approaching this correctly? I'm guessing I need to just improve my nested select statement in my merge to join the ATTRIBUTE_MAP and PEER_GROUP_DEFINTIONS and then go from there. Any help/suggestions would be appreciated.
Here's an example for reference:
ATTRIBUTE_MAP:
+---------+--------------+------------+
| CUST_ID | ATTRIBUTE_ID | VALUE |
+---------+--------------+------------+
| 50 | 1 | 'New York' |
+---------+--------------+------------+
| 50 | 2 | |
+---------+--------------+------------+
GROUP_DEFINITIONS:
+----------+-------------+------------+-------------+---------+-------------+---------+
| GROUP_ID | ATTRIBUTE_1 | VALUE_1 | ATTRIBUTE_2 | VALUE_2 | ATTRIBUTE_3 | VALUE_3 |
+----------+-------------+------------+-------------+---------+-------------+---------+
| 10 | 1 | 'New York' | 2 | | | |
+----------+-------------+------------+-------------+---------+-------------+---------+
| 20 | 2 | | | | | |
+----------+-------------+------------+-------------+---------+-------------+---------+
and so the script should generate (in GROUP_MAP):
+---------+----------+--------+
| CUST_ID | GROUP_ID | DATE |
+---------+----------+--------+
| 50 | 10 | *date* |
+---------+----------+--------+
| 50 | 20 | *date* |
+---------+----------+--------+

Answer 1

I could be totally off, but it looks like your inner select needs to be something like this. If I understand what you are trying to do, this will return a unique list of CUST_ID, GROUP_ID, START_DATE where all of the customer attributes match all of the group attributes. Just wrote this fast, so might have some errors, but it might get you going the right direction.
with gd as (
SELECT GROUP_ID, ATTRIBUTE_1 as ATTRIBUTE_ID, VALUE_1 as VALUE from GROUP_DEFINITIONS
UNION
SELECT GROUP_ID, ATTRIBUTE_2, VALUE_2 from GROUP_DEFINITIONS
UNION
SELECT GROUP_ID, ATTRIBUTE_3, VALUE_3 from GROUP_DEFINITIONS
)
MERGE GROUP_MAP gm
USING
(
SELECT am.CUST_ID, gd.GROUP_ID, am.START_DATE
FROM ATTRIBUTE_MAP am
JOIN gd
ON am.ATTRIBUTE_ID = gd.ATTRIBUTE_ID AND coalesce(am.VALUE, '') = coalesce(gd.VALUE, '')
join (select GROUP_ID, count(*) as ATTR_COUNT from gd where ATTRIBUTE_ID is NOT NULL group by GROUP_ID) as gc
on gd.GROUP_ID = gc.GROUP_ID
GROUP BY am.CUST_ID, gd.GROUP_ID, am.START_DATE
HAVING count(am.ATTRIBUTE_ID) = max(gc.ATTR_COUNT)
) src
ON gm.GROUP_ID = src.GROUP_ID
AND gm.CUST_ID = src.CUST_ID
WHEN NOT MATCHED
THEN -- create association in GROUP_MAP
INSERT(CUST_ID,
GROUP_ID,
FROM_DATE) VALUES
(src.CUST_ID, src.GROUP_ID, src.START_DATE);

Answer 2

If I understood the problem correctly this should do it:
Please note I have used GETDATE() as I do not have the field [START_DATE] but you will need to substitute this within the code
SAMPLE DATA:
CREATE TABLE #ATTRIBUTE_MAP(CUST_ID INT,
ATTRIBUTE_ID INT,
VALUE VARCHAR(20));
INSERT INTO #ATTRIBUTE_MAP
VALUES
(50, 1, 'New York'),
(50, 2, NULL);
CREATE TABLE #GROUP_DEFINITIONS(GROUP_ID INT,
ATTRIBUTE_1 INT,
VALUE_1 VARCHAR(20),
ATTRIBUTE_2 INT,
VALUE_2 VARCHAR(20),
ATTRIBUTE_3 INT,
VALUE_3 VARCHAR(20));
INSERT INTO #GROUP_DEFINITIONS
VALUES
(10, 1, 'New York', 2, NULL, NULL, NULL),
(20, 2, NULL, NULL, NULL, NULL, NULL);
CREATE TABLE #GROUP_MAP(CUST_ID INT,
GROUP_ID INT,
[FROM_DATE] DATE);
QUERY:
MERGE #GROUP_MAP gm
USING
(SELECT DISTINCT
am.CUST_ID,
CAST(GETDATE() AS DATE) AS [START_DATE], --<-- you will need to change this
gd.GROUP_ID
FROM #ATTRIBUTE_MAP am
INNER JOIN
(
SELECT GROUP_ID,
ATTRIBUTE_1 AS ATTRIBUTE_ID,
VALUE_1
FROM #GROUP_DEFINITIONS
UNION ALL
SELECT GROUP_ID,
ATTRIBUTE_2,
VALUE_2
FROM #GROUP_DEFINITIONS
UNION ALL
SELECT GROUP_ID,
ATTRIBUTE_3,
VALUE_3
FROM #GROUP_DEFINITIONS) gd ON am.ATTRIBUTE_ID = gd.ATTRIBUTE_ID) src
ON gm.GROUP_ID = src.GROUP_ID
AND gm.CUST_ID = src.CUST_ID
WHEN NOT MATCHED
THEN -- create association in GROUP_MAP
INSERT(CUST_ID,
GROUP_ID,
FROM_DATE) VALUES
(src.CUST_ID, src.GROUP_ID, src.START_DATE);
VERIFY RESULT:
SELECT CUST_ID , GROUP_ID , FROM_DATE
FROM #GROUP_MAP;
RESULT: