Question

I have a table that has an ID field with a trigger (so it's essentially an IDENTITY field) as my primary key. I mostly don't care about that.

The rest of the data are several linking keys, and I want to query my data, and if any of those keys have changed, add a new record with a new effective date. If all the keys are the same, then nothing should be added.

However, even when all of the keys match, it is adding new records. All of the fields I care about are exactly the same, so I'm essentially getting duplicate records, but with a new ID and new effective date.

I'll simplify my code a bit, but this is essentially what I have:

MERGE_TABLE (
merge_ID  NUMBER(18) PRIMARY KEY NOT NULL,
asof_Date  Date,
keyA  varchar2(10 byte),
keyB  varchar2(10 byte),
keyC  varchar2(10 byte),
table_date Date)

There is a trigger on merge_ID on insert to use a sequence.

MERGE INTO merge_table mt
USING (
    select keyA, keyB, keyC, table_date
    from table  -- it's actually a complex query, but it's getting data
      ) tbl
ON (rtrim(tbl.keyA) = rtrim(mt.keyA)
   AND rtrim(tbl.keyB) = rtrim(mt.keyB) 
   AND rtrim(tbl.keyC) = rtrim(mt.keyC))
WHEN NOT MATCHED THEN
   INSERT (asof_Date, keyA, keyB, keyC, table_date)
   VALUES (sysdate, tbl.keyA, tbl.keyB, tbl.keyC, tbl.table_date)

If my MERGE_TABLE starts with the following data:

merge_ID    asof_Date   keyA   keyB   keyC  table_date
  10        1/1/2018    333    456    987    12/31/2017
  11        1/1/2018    444    234    876    12/31/2017
  12        1/1/2018    222    789    654    12/31/2017

then, after running it, I have the following data:

merge_ID    asof_Date   keyA   keyB   keyC  table_date
  10        1/1/2018    333    456    987    12/31/2017
  11        1/1/2018    444    234    876    12/31/2017
  12        1/1/2018    222    789    654    12/31/2017
  13        3/22/2018   333    456    987    12/31/2017
  14        3/22/2018   444    234    876    12/31/2017
  15        3/22/2018   222    789    654    12/31/2017

My keys all matched, but it did an insert anyway. Why?

If KeyB had changed on the first record from 456 to 678, the data I would want is:

merge_ID    asof_Date   keyA   keyB   keyC  table_date
  10        1/1/2018    333    456    987    12/31/2017
  11        1/1/2018    444    234    876    12/31/2017
  12        1/1/2018    222    789    654    12/31/2017
  13        3/22/2018   333    678    987    12/31/2017

Oracle merge adding records when matched

0 个答案: