Re: INSERT Trigger to check for existing records

Adrian and Michael,

My current insert logic (which works) is in a psycopg2 python script which reads a spreadsheet row into an array, so for the moment I didn't want to add that integration to my struggle.

cur = conn.cursor()
                                                                                                                                                                                                                      \
query = "INSERT INTO sfdc(theater,country,account,smotion,opname,cprod,opid,ndealid,qnum,stage,revusd,cdate,bdate,age,opown,opnum,sonum,fbdate,region,dqnum,pid,closed,won,onum,repdate)

VALUES (%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s);"
                                   
cur.executemany(query, frecords)
conn.commit()
conn.close()

However, the following is something of a stepping stone towards the destination and, (dare I say it? ;-) it works:

CREATE OR REPLACE FUNCTION same_test(did numeric)
RETURNS numeric AS $$
BEGIN
  IF $1 IN
      (SELECT ndealid from hygiene_112)
  THEN
    UPDATE hygiene_119 SET paid = 'SAME';
  ELSE
      UPDATE hygiene_119 SET paid = 'NEW';
  END IF;
RETURN NULL;
END;
$$ LANGUAGE plpgsql;

I changed the dealid to something that doesn't exist (14593030) in the 11-2 table and the function updates the 11-9 table.status field to "NEW":

sales=# UPDATE hygiene_112 SET ndealid = 14593030 WHERE ndealid = 14593039;
UPDATE 1

SELECT same_test(14593039);

+----------+-----------------------------------+------------------------------------------------------+--------+----------+----------------------+------+
|repdate   |ndealid |revusd    |stage                 |status  |
+----------+-----------------------------------+------------------------------------------------------+--------+----------+----------------------+------+
|2020-11-09|14593039|1015624.23|Propose - 60%         |NEW   |
+----------+-----------------------------------+------------------------------------------------------+--------+----------+----------------------+------+

When I changed it back I get the proper "SAME" update:

sales=# UPDATE hygiene_112 SET ndealid = 14593039 WHERE ndealid = 14593030;
UPDATE 1

SELECT same_test(14593039);

+----------+-----------------------------------+------------------------------------------------------+--------+----------+----------------------+------+
|repdate   |ndealid |revusd    |stage                 |status  |
+----------+-----------------------------------+------------------------------------------------------+--------+----------+----------------------+------+
|2020-11-09|14593039|1015624.23|Propose - 60%         |SAME   |
+----------+-----------------------------------+------------------------------------------------------+--------+----------+----------------------+------+

I'm generally amazed when ANYTHING works so this is good news (to me). It seems logical I could replace the UPDATE statement with an INSERT statement at this point.

However, that only addresses one of the data rules on my checklist.

I'll keep forging ahead here and see what additional progress I can attain. Very much appreciate your patient assistance here.

Best,

Hagen

On 11/22/20 9:53 AM, Hagen Finley wrote:

Hello Michael,

Thanks so much for this advice. As I mentioned previously, I'm not very good at this yet, so forgive me if my response is obtuse. I really love databases but my sentiments may be unrequited.

The overriding issue is lack of a plan. From your first post:

"Here’s what I (REALLY) want:


Trigger looks at three fields prior to new insert: Deal ID (numeric),
revenue (numeric), stage(char)     Example: 19743576 22072.37    Commit
- 90%


 1. If the NEW dealid doesn't match any of the OLD dealids, insert the
    new row
 2. if the NEW dealid, revenue and stage fields ALL match the OLD
    dealid, revenue and stage, skip (don't insert the NEW row)
 3. If the NEW dealid matches an OLD dealid but either the NEW revenue
    OR the stage fields have changed (don't match OLD record) insert new
    row (I'll review both rows manually)
"

And from later post:

" I figure I could
use the chk field to delete the new inserts I didn't need."


From this I come up with the following:

1) Data rules

  a) If dealid in new data does not exist in old data INSERT row.
  b) Id dealid is in both new and old data AND revenue OR stage don't  match then INSERT and mark for review.
  c) If new dealid, revenue, stage match old dealid, revenue, stage then do not INSERT.

2) Process the data. Choices
   a) Use trigger on table sfdc
   b) Use staging table to hold new data and then process into sfdc table

3) Process the data. Same basic principle for both choices in 2) Flowchart
   a) In new data search for dealid in table sfdc if it does not exist add data to sfdc.
   b) If new data dealid does exist in sfdc
    1) If revenue or stage field differ mark for review
    2) If they do match skip further processing
4) Thoughts about above.
   a) To me table sfdc should only hold vetted data that is known to be unique per row.
   b) The data for review  1)b) 3)b) should end up in another review table e.g. sfdc_review.
   c) Since from OP ' 80% of the records are
the same as the existing records from the week before.' it makes sense to use the staging table 2)b) process rather then throwing away a lot of INSERTs.

If this makes sense then it comes down to decision in which choice in 2) to use. At that point it is filling in the flowchart with the exact steps to take.

In reality my table has lots of columns (~30) including a report date (repdate) and each week's pull has a new repdate ( in this case 2020-11-02 and 2020-11-09) which could function as a "created on" field.

To clarify, I would create an unique index on all the columns in the old report records (2020-11-02)  or just the three I am comparing (dealid,stage and revenue)?

In either case, so far in my efforts it looks like the create index fails because there are lots of rows with the same stage value, and a few with the same revenue value.

Create UNIQUE INDEX idx_sfdc
ON sfdc(ndealid, stage, revusd);

ERROR: could not create unique index "idx_sfdc" DETAIL: Key (ndealid, stage, revusd)=(19743576, Commit - 90% , 22072.37) is duplicated. SQL state: 23505

I probably could create an unique index on the dealid column as that should be unique. Would that be enough? It seems like that would insert ONLY the new records with a new (unique) dealid and that would definitely by an important step forward.

I hesitate to admit I have no idea how I would code the "call insert on conflict (unique index) do nothing" syntax, but I would be excited to learn.

Best,

Hagen


On 11/22/20 8:54 AM, Michael Lewis wrote:

If you can modify your insert statement, and live with an extra column in the data, no trigger is needed as best I can figure.

Create a unique index over the existing columns, add a "created_on" field and call insert on conflict (unique index) do nothing.

This should give the behavior you want.