Delta load logic using oracle merge/delete sql statement

user12251389 · January 19

I have table TEST_RUA where i am importing data daily. I am using Truncate and Insert logic for this table. Now i have another table TEST_RUA_MER same like table TEST_RUA where i want to apply Delta load logic. There is always unique combination of column values ID_LL, ID_UU, TKR in both table.

The Delta logic should be:

For Update: i want to compare the data from table TEST_RUA_MER and TEST_RUA and then update the table TEST_RUA_MER only when there is unique combination of column values ID_LL, ID_UU, TKR exist in both table and when there is change in any field value in table TEST_RUA. We can also introduce new column called status and update the status as 'UPD' for this rows so that we can filter out data in View if required.

For Insert: if there is no unique combination of column values ID_LL, ID_UU, TKR exist in table TEST_RUA_MER but exist in table TEST_RUA then insert the data into table TEST_RUA_MER.

For Delete: The Delete statement can be done separately. We have to use Delete statement to delete the data from table TEST_RUA_MER which does not exist in table TEST_RUA while using unique combination of columns ID_LL, ID_UU, TKR and also delete data from table TEST_RUA_MER which is equal in table TEST_RUA. So in table TEST_RUA_MER i just only want to keep updated and new data from table TEST_RUA. If Delete not possible we can also create just View to filter out the data if possible.

Can it be achieved with single merge statement and delete statement separately or is there any other logic we can implement? I dont want to use pl/sql for this logic. But i can also use Sql View for any comparision condition because at the end i just want to generate csv report with the delta load table.

Below is sql fiddle for create and insert statement: https://dbfiddle.uk/?rdbms=oracle_18&fiddle=fef3ef12dbcb8c286cf9a5845d9fabd3

Below is the sql statements :

Create statement for TEST_RUA table:

Create table TEST_RUA (CLASS VARCHAR2(100), ID_LL VARCHAR2(100), ID_UU VARCHAR2(100), TKR VARCHAR2(100), NAME VARCHAR2(100))

Insert statement for TEST_RUA table:

INSERT INTO TEST_RUA VALUES ('Bond', 'BERF', 'GV9999B12M1', 'TKXX', 'TES_RES');
INSERT INTO TEST_RUA VALUES ('Bond', 'BERT', 'FV9999B12M3', 'BURR', 'PRS_RES');
INSERT INTO TEST_RUA VALUES ('Bond', 'BREG', 'TV9999B12M4', 'CVKR', 'FRTG_OP');
INSERT INTO TEST_RUA VALUES ('Bond', 'BREG', 'SQTUREGBFNO', 'LRQU', 'BEGT_TU');
INSERT INTO TEST_RUA VALUES ('Bond', 'TREW', 'BTREUIOPDFG',  null,  'LOPIU');
INSERT INTO TEST_RUA VALUES ('Bond',  null,  'LOPUITRDSFG', 'FTGR',  'MKDER');

Create statement for TEST_RUA_MER table:

Create table TEST_RUA_MER (CLASS VARCHAR2(100), ID_LL VARCHAR2(100), ID_UU VARCHAR2(100), TKR VARCHAR2(100), NAME VARCHAR2(100));

Insert statement for TEST_RUA_MER table:

    INSERT INTO TEST_RUA_MER VALUES ('Bond', 'BERF', 'GV9999B12M1', 'TKXX', 'TES_RES');
    INSERT INTO TEST_RUA_MER VALUES ('Bond', 'BERT', 'FV9999B12M3', 'BURR', 'PRS_RES');
    INSERT INTO TEST_RUA_MER VALUES ('Bond', 'BREG', 'TV9999B12M4', 'CVKR', 'MT_QUE');
    INSERT INTO TEST_RUA_MER VALUES ('Bond', 'BREG', 'LV9999B12F6', 'OPTQ', 'BWQT_UI');

Expected output in table TEST_RUA_MER. Please note that the value from either ID_LL or ID_UU or TKR can be null. So we also need to check this unique combination.

CLASS   ID_LL   ID_UU       TKR     NAME
Bond    BREG    TV9999B12M4 CVKR    FRTG_OP
Bond    BREG    SQTUREGBFNO LRQU    BEGT_TU
Bond    TREW    BTREUIOPDFG NULL    LOPIU
Bond    null    LOPUITRDSFG FTGR    MKDER

Frank Kulash · January 19

Hi,

I have edited the question and in the expected output ...

Please don't ever change your messages after you post them: it makes the thread hard to follow and it makes your changes easy to miss. Make all corrections and additions in a new message. (It's okay to add something like "EDIT: new sample data and results are posted below", but that's the only kind of change you should make to an existing message.)

Can you please update your query here accordingly.

You just need to change the conditions in the ON clause, like this:

MERGE INTO test_rua_mer dst
USING (
      SELECT  id_ll, id_uu, tkr
      ,	   tr.class, tr.name -- Plus any additional columns
	  ,     CASE
	         WHEN tr.ROWID IS NULL
			 OR  (  DECODE (tr.class, trm.class, 'SAME') = 'SAME'
			    AND DECODE (tr.name, trm.name, 'SAME') = 'SAME'
              -- AND ... -- the same for any additional columns
				)
			 THEN 'DELETE'
	       END  AS delete_flag
      FROM   test_rua   tr
      FULL JOIN test_rua_mer trm USING (id_ll, id_uu, tkr)
    )         src
ON (  DECODE (src.id_ll, dst.id_ll, 'SAME') = 'SAME'
  AND DECODE (src.id_uu, dst.id_uu, 'SAME') = 'SAME'
  AND DECODE (src.tkr,   dst.tkr,   'SAME') = 'SAME'
  )
WHEN NOT MATCHED
THEN INSERT (dst.class, dst.id_ll, dst.id_uu, dst.tkr, dst.name) -- plus any additional columns
     VALUES (src.class, src.id_ll, src.id_uu, src.tkr, src.name) -- plus any additional columns
WHEN MATCHED THEN UPDATE
  SET dst.class = src.class
  ,   dst.name  = src.name
-- ,  ...  -- the same for any additional column
DELETE WHERE src.delete_flag = 'DELETE'
;

Aside from the three lines in the ON clause and comments, this is exactly what I posted in my previous message.

I actually dont understand the below part :

CASE

WHEN tr.ROWID IS NULL

OR ( DECODE (tr.class, trm.class, 'SAME') = 'SAME'

AND DECODE (tr.name, trm.name, 'SAME') = 'SAME'

)

THEN 'DELETE'

END AS delete_flag

This defines a column in dst called delete_flag, which will have the value 'DELETE' when either

a row in test_rua_mer has no match in test_rua (that's the only time when tr.ROWID will be NULL, assuming test_rua is a real table), OR
both the class and name columns are the same in both tables (where both being NULL counts as the same, but exactly one being NULL does not)

These are the conditions for an existing row in test_rua_mer to be deleted. This value will be used in the DELETE WHERE clause, which is your next question.

And also this part:

DELETE WHERE src.delete_flag = 'DELETE'

This tells MERGE to DELETE any row in the destination table that had a matching row in the source "table" with delete_flag equal to the six-character string 'DELETE'.

If i add more fields in table where the field value might be null then it should not be problem with the query or do i need to handle it separately and how. ? I think if we just add those fields in Decode part will be sufficient ?

If you have more columns like class and name, then change every place in the query that mentions class and name to mention the additional columns the same way. See the comments in the code above.

JonWat · January 19

The merge below should do what you want. In the query for the merge the MINUS subtracts out all the rows that are unchanged from those in test_rua_mer. That's a fairly expensive operation: it has to compare all of the columns in one table with all of the columns in another, so if you had a cheaper way (like an update date or soemthing) to determine if the test_rua rows should be treated as changed, that would probably be better.

merge into test_rua_mer t USING

(select *

from test_rua

MINUS

select *

from test_rua_mer

) q

on (t.id_ll= q.id_ll and t.id_uu = q.id_uu and t.tkr = q.tkr)

when matched then update set class = q.class,name = q.name

when not matched then insert values(q.class,q.id_ll,q.id_uu,q.tkr,q.name);

user12251389 · January 19

But how do i get only two rows at the end as mentioned in the expected output because this is what i need for select statement at the end...can we create view to filter out the data or i think we might need delete to maintain the table TEST_RUA_MER ? Because for example now during next import in TEST_RUA table if row 'Bond', 'BERF', 'GV9999B12M1', 'TKXX', 'TES_RES' does not exist but its already there in table TEST_RUA_MER then how can we filter this out from table TEST_RUA_MER as Merge will not be sufficient in this case ? Also we only need updated rows at the end in table TEST_RUA_MER for example mentioned in the expected output as Bond BREG TV9999B12M4 CVKR FRTG_OP . How do we get that in select statment?

https://community.oracle.com/tech/developers/discussion/comment/16781846#Comment_16781846

Frank Kulash · January 19

Hi, @user12251389

Here's one way to do it:

MERGE INTO test_rua_mer dst
USING (
      SELECT  id_ll, id_uu, tkr
      ,	   tr.class, tr.name
      ,    CASE
	           WHEN tr.ROWID IS NULL
			 OR  (  LNNVL (tr.class <> trm.class)
			     AND LNNVL (tr.name <> trm.name)
			     )
		   THEN 'DELETE'
	   END  AS delete_flag
      FROM      test_rua     tr
      FULL JOIN test_rua_mer trm  USING (id_ll, id_uu, tkr)
    )         src
ON (  src.id_ll = dst.id_ll
   AND src.id_uu = dst.id_uu
   AND src.tkr   = dst.tkr
   )
WHEN NOT MATCHED
THEN INSERT (dst.class, dst.id_ll, dst.id_uu, dst.tkr, dst.name)
     VALUES (src.class, src.id_ll, src.id_uu, src.tkr, src.name)
WHEN MATCHED THEN UPDATE
  SET dst.class = src.class
  ,   dst.name  = src.name
DELETE WHERE src.delete_flag = 'DELETE'
;

This will update (rather than delete) when one table has a value in either class or name, and the other table has a matching row with NULL in the same column. (I assume that's what you mean by "when there is change".) y doesn't do whaT YOU WANT

EDIT: This may not do what you want when class and/or name is NULL. See my next message below.

By the way, CLASS and NAME are Oracle keywords. Using them as column names can cause problems.

JonWat · January 19

I think I understand what you are asking, but maybe I'm not.

In your example you have four existing rows in test_rua_mer and your process should add two rows. I think what you want to do is export just those two rows you added somewhere else, but the next time you run the process, those two rows are just part of the "existing" test_rua_mer, the same as the four rows are currently, and you won;t want to print/export them.

So I think what you need to do is add a "flag" column to test_rua_mer that says: this is a new row for printing, and when you print you reset that to null or zero to indicate it is not new any more.

Paulzip · January 19

You can determine your actions with the following query, and plug that into the merge or update statements.

This is based on a template approach by Stew Ashton, he has a package for doing delta changes on his blog.

select CLASS, ID_LL, ID_UU, TKR,
    count(*) over (partition by ID_LL, ID_UU, TKR) - sum(Z##CNT) Z##IUD_FLAG
    /* Z##IUD_FLAG
      0 : Insert. In source, not in destination
      1 : Update. New, from source to destination
      2 : Delete. Not in source, in destination
      3 : Update. Old from destination to source (generally not used)
    */     
from (
 select CLASS, ID_LL, ID_UU, TKR, -1 Z##CNT -- Target
 from TEST_RUA_MER
 union all
 select CLASS, ID_LL, ID_UU, TKR, 1 Z##CNT -- Source
 from TEST_RUA n  
)
group by CLASS, ID_LL, ID_UU, TKR

Frank Kulash · January 19

Hi,

I just tested with some NULL data. What do you want with this:

INSERT INTO TEST_RUA     VALUES (NULL, 'F1', 'F1', 'F1', NULL);
INSERT INTO TEST_RUA_MER VALUES (NULL, 'F1', 'F1', 'F1', NULL);
INSERT INTO TEST_RUA     VALUES (NULL, 'F2', 'F2', 'F2', 'A');
INSERT INTO TEST_RUA_MET VALUES (NULL, 'F2', 'F2', 'F2' NULL);

? If you want the row in test_rua_mer with id_ll='F1' to be deleted (because there was no change in the class and name columns) but you want the row in test_rua_mer with id_ll='F2' to be updated (because name changed from NULL to 'A') then do this:

MERGE INTO test_rua_mer dst
USING (
      SELECT  id_ll, id_uu, tkr
      ,	   tr.class, tr.name
	  ,     CASE
	         WHEN tr.ROWID IS NULL
			 OR  (  DECODE (tr.class, trm.class, 'SAME') = 'SAME'
			    AND DECODE (tr.name, trm.name, 'SAME') = 'SAME'
				)
			 THEN 'DELETE'
	       END  AS delete_flag
      FROM   test_rua   tr
      FULL JOIN test_rua_mer trm USING (id_ll, id_uu, tkr)
    )         src
ON (  src.id_ll = dst.id_ll
  AND src.id_uu = dst.id_uu
  AND src.tkr  = dst.tkr
  )
WHEN NOT MATCHED
THEN INSERT (dst.class, dst.id_ll, dst.id_uu, dst.tkr, dst.name)
   VALUES (src.class, src.id_ll, src.id_uu, src.tkr, src.name)
WHEN MATCHED THEN UPDATE
  SET dst.class = src.class
  ,  dst.name  = src.name
DELETE WHERE src.delete_flag = 'DELETE'
;

This is the same as the MERGE I posted earlier, except the two lines that used LNNVL to handle NULL have been changed to use DECODE instead.

The two statements behave the same when class and name are not NULL.

user12251389 · January 19

https://community.oracle.com/tech/developers/discussion/comment/16781853#Comment_16781853

Thanks its working the way expected.. In the On clause you didnt check for null ...because sometime any of the value from id_ll or id_uu, tkr might be null. I really

I really dont know how this Merge is deleting/updating the data from table TEST_RUA_MER can you please explain ? Because if i run merge many times then i get different output in table TEST_RUA_MER see https://dbfiddle.uk/?rdbms=oracle_18&fiddle=d6cc6fe1f57ca3368057f99db236c3b2 So it looks like i dont need any Delete statement here ...

Last point EDIT: This may not do what you want when class and/or name is NULL. Sorry i dont understand here. Actually this column and values are coming from flat file so i need to keep this columns. Do you think its problem if they are null ? I just tested and you are right its failing somehow when the value is null for Class or Name field. Is there any solution on this...I can remove field Name but i need Class field in table..

user12251389 · January 19

https://community.oracle.com/tech/developers/discussion/comment/16781860#Comment_16781860

@Paulzip i think for this we need PL/SQL package to trigger Insert or Update or Delete statament unfortuantely i dont want to create Pl/SQL package

user12251389 · January 19

https://community.oracle.com/tech/developers/discussion/comment/16781855#Comment_16781855

Yes with flag also we can do this...i can add new field but will it be possible then with merge statment ?

user12251389 · January 19

https://community.oracle.com/tech/developers/discussion/comment/16781863#Comment_16781863

Will it be problem if in Update clause i also use condition as dst.id_uu = src.id_uu , dst.id_ll = src.id_ll , dst.id_tkr = src.id_tkr ?

Paulzip · January 19

https://community.oracle.com/tech/developers/discussion/comment/16781868#Comment_16781868

No you don't. Merge statements can have where clauses on the insert / update / delete clause. The where would refer to the flag to decide which to process.

Frank Kulash · January 19

Hi, @user12251389

On clause you didnt check for null ...because sometime any of the value from id_ll or id_uu, tkr might be null. I really

The query I posted above assumed id_ll, id_uu and tkr are not NULL. If they can be NULL, then include examples in your sample data, results and explantion. You probably just need to replace

dst.x = src_x

with

DECODE (dst.x, src.x, 'SAME') = 'SAME'

I really dont know how this Merge is deleting/updating the data from table TEST_RUA_MER can you please explain ?

I'll be glad to explain, but what exactly do you want me to explain? It would save you (as well as me) a lot of time if you asked a more specific question about the part(s) you don't understand.

Whenever you're trying to understand a MERGE statement, it helps if you execute the USING clause all by itself. Study the output of the USING query and make sure you understand it.

So it looks like i dont need any Delete statement here ...

No, you don't need a separate DELETE statement. MERGE can DELETE rows as well as INSERT or UPDATE them.

Last point EDIT: This may not do what you want when class and/or name is NULL. Sorry i dont understand here. Actually this column and values are coming from flat file so i need to keep this columns. Do you think its problem if they are null ?

If you can have NULLs, then include examples of NULLs in the sample data, and how NULLs need to be handled in the desired results and explanation that you post. There's nothing you've said so far that suggest NULLs would make the job impossible.

user12251389 · January 19

https://community.oracle.com/tech/developers/discussion/comment/16781876#Comment_16781876

I have edited the question and in the expected output part i have added explaination and also edited the output as the value from either ID_LL or ID_UU or TKR can be null. So we also need to check this unique combination.

Can you please update your query here accordingly. I actually dont understand the below part :

CASE

WHEN tr.ROWID IS NULL

OR ( DECODE (tr.class, trm.class, 'SAME') = 'SAME'

AND DECODE (tr.name, trm.name, 'SAME') = 'SAME'

)

THEN 'DELETE'

END AS delete_flag

And also this part:

DELETE WHERE src.delete_flag = 'DELETE'

If i add more fields in table where the field value might be null then it should not be problem with the query or do i need to handle it separately and how. ? I think if we just add those fields in Decode part will be sufficient ?

user12251389 · January 19

https://community.oracle.com/tech/developers/discussion/comment/16781875#Comment_16781875

thanks Paul do you have an example of this ?

Frank Kulash · January 19

Hi,

I have edited the question and in the expected output ...

Please don't ever change your messages after you post them: it makes the thread hard to follow and it makes your changes easy to miss. Make all corrections and additions in a new message. (It's okay to add something like "EDIT: new sample data and results are posted below", but that's the only kind of change you should make to an existing message.)

Can you please update your query here accordingly.

You just need to change the conditions in the ON clause, like this:

MERGE INTO test_rua_mer dst
USING (
      SELECT  id_ll, id_uu, tkr
      ,	   tr.class, tr.name -- Plus any additional columns
	  ,     CASE
	         WHEN tr.ROWID IS NULL
			 OR  (  DECODE (tr.class, trm.class, 'SAME') = 'SAME'
			    AND DECODE (tr.name, trm.name, 'SAME') = 'SAME'
              -- AND ... -- the same for any additional columns
				)
			 THEN 'DELETE'
	       END  AS delete_flag
      FROM   test_rua   tr
      FULL JOIN test_rua_mer trm USING (id_ll, id_uu, tkr)
    )         src
ON (  DECODE (src.id_ll, dst.id_ll, 'SAME') = 'SAME'
  AND DECODE (src.id_uu, dst.id_uu, 'SAME') = 'SAME'
  AND DECODE (src.tkr,   dst.tkr,   'SAME') = 'SAME'
  )
WHEN NOT MATCHED
THEN INSERT (dst.class, dst.id_ll, dst.id_uu, dst.tkr, dst.name) -- plus any additional columns
     VALUES (src.class, src.id_ll, src.id_uu, src.tkr, src.name) -- plus any additional columns
WHEN MATCHED THEN UPDATE
  SET dst.class = src.class
  ,   dst.name  = src.name
-- ,  ...  -- the same for any additional column
DELETE WHERE src.delete_flag = 'DELETE'
;

Aside from the three lines in the ON clause and comments, this is exactly what I posted in my previous message.

I actually dont understand the below part :

CASE

WHEN tr.ROWID IS NULL

OR ( DECODE (tr.class, trm.class, 'SAME') = 'SAME'

AND DECODE (tr.name, trm.name, 'SAME') = 'SAME'

)

THEN 'DELETE'

END AS delete_flag

This defines a column in dst called delete_flag, which will have the value 'DELETE' when either

a row in test_rua_mer has no match in test_rua (that's the only time when tr.ROWID will be NULL, assuming test_rua is a real table), OR
both the class and name columns are the same in both tables (where both being NULL counts as the same, but exactly one being NULL does not)

These are the conditions for an existing row in test_rua_mer to be deleted. This value will be used in the DELETE WHERE clause, which is your next question.

And also this part:

DELETE WHERE src.delete_flag = 'DELETE'

This tells MERGE to DELETE any row in the destination table that had a matching row in the source "table" with delete_flag equal to the six-character string 'DELETE'.

If i add more fields in table where the field value might be null then it should not be problem with the query or do i need to handle it separately and how. ? I think if we just add those fields in Decode part will be sufficient ?

If you have more columns like class and name, then change every place in the query that mentions class and name to mention the additional columns the same way. See the comments in the code above.

user12251389 · January 19

https://community.oracle.com/tech/developers/discussion/comment/16781890#Comment_16781890

Thanks very much @Frank Kulash I understand your query now and it works perfectly...i will update in case any question :)

Paulzip · January 19

The problem with Frank's approach is it isn't very scalable. It'll work fine if your dataset is small, but I suspect you'll see performance issues as you increase rows to larger sets. My approach as the basis of a merge is much more scalable.

user12251389 · January 19

https://community.oracle.com/tech/developers/discussion/comment/16781893#Comment_16781893

I have like 700000k rows in my table..i need to check the performance with Franks merge query with this datasets now..@Paulzip can you please provide merge query with your example ..i really would be interested to test

user12251389 · January 20

https://community.oracle.com/tech/developers/discussion/comment/16781890#Comment_16781890

@Paulzip i tried with now huge dataset like 700000k rows and i am getting error as ORA-08006: specified row no longer exists

I dont have any clue why its failing and i cannot even post here such dataset for testing. Do you have any idea why Merge is failing and what needs to be changed. I checked in some forums that you need to create Unique key for such issues and i tried but same error?

user12251389 · January 20

https://community.oracle.com/tech/developers/discussion/comment/16781893#Comment_16781893

@Paulzip Can you please provide Merge query from your solution as currently i am getting error when i tried with huge dataset as ORA-08006: specified row no longer exists

Solomon Yakobson · January 20

MERGE
  INTO TEST_RUA_MER T
  USING (
         SELECT  T.ROWID T_RID,
                 CASE
                   WHEN S.ROWID IS NULL THEN 1
                   WHEN     DECODE(S.CLASS,T.CLASS,1) = 1
                        AND
                            DECODE(S.NAME,T.NAME,1) = 1
                     THEN 1
                 END DELETE_FLAG,
                 S.*
           FROM      TEST_RUA S
                 FULL JOIN
                     TEST_RUA_MER T
                   ON(
                          DECODE(T.ID_LL,S.ID_LL,1) = 1
                      AND
                          DECODE(T.ID_UU,S.ID_UU,1) = 1
                      AND
                          DECODE(T.TKR,S.TKR,1) = 1
                     )
        ) S
  ON (
          T.ROWID = S.T_RID
     )
  WHEN MATCHED
    THEN
      UPDATE
         SET T.CLASS = S.CLASS,
             T.NAME  = S.NAME
      DELETE WHERE S.DELETE_FLAG = 1
  WHEN NOT MATCHED
    THEN
      INSERT
      VALUES(
             S.CLASS,
             S.ID_LL,
             S.ID_UU,
             S.TKR,
             S.NAME
            )
/


7 rows merged.


SQL> SELECT  *
  2    FROM  TEST_RUA_MER
  3    ORDER BY CLASS,
  4             ID_LL,
  5             ID_UU,
  6             TKR,
  7             NAME
  8  /


CLASS ID_LL ID_UU       TKR  NAME
----- ----- ----------- ---- -------
Bond  BREG  SQTUREGBFNO LRQU BEGT_TU
Bond  BREG  TV9999B12M4 CVKR FRTG_OP
Bond  TREW  BTREUIOPDFG      LOPIU
Bond        LOPUITRDSFG FTGR MKDER


SQL>

However, keep in mind DELETE clause of WHEN MATCHED UPDATE is executed after update. So if there is large number of to be deleted rows and performance is important I wouldn't use MERGE since, as I already mentioned, such rows will be first updated and only then deleted.

SY.

user12251389 · January 20

https://community.oracle.com/tech/developers/discussion/comment/16781991#Comment_16781991

@Solomon Yakobson the query logic is fine..i tested with dummy small datasets.. but currently for 800000k records the its taking more than 30 minutes and its still running which is problem...how can we improve performance in this Merge query ?

Why are we using Decode function function instead of just checking if the values are equal. I think may be this is causing perfromance issue?

Solomon Yakobson · January 20

We use DECODE because it treats two NULLs as equal. Otherwise we would have to use:

                   ON(
                          (T.ID_LL = S.ID_LL OR (T.ID_LL IS NULL AND S.ID_LL IS NULL))
                      AND
                          (T.ID_UU = S.ID_UU OR (T.ID_UU IS NULL AND S.ID_UU IS NULL))
                      AND
                          (T.TKR = S.TKR OR (T.TKR IS NULL AND S.TKR IS NULL))
                     )

You could try creating function based indexes in both tables on '|' || ID_LL || |' || ID_UU || |' || TKR || '|' (assuming | can'appear in these columns) and then use

ON (
    '|' || S.ID_LL || '|' || S.ID_UU || '|' || S.TKR || '|' = '|' || T.ID_LL || '|' || T.ID_UU || '|' || T.TKR || '|'
   )

SY.

Forum Stats

Howdy, Stranger!

Quick Links

Categories

Delta load logic using oracle merge/delete sql statement

Best Answer

Answers

Data

Databases

Development

Development Tools

Open Source

Programs

Forum Stats

Howdy, Stranger!

Categories

Delta load logic using oracle merge/delete sql statement

Best Answer

Answers