Why Fload doesn’t support multiset table?
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Answer / rajneesh
FastLoad support Multiset table but does not support the
duplicate rows.
Multiset tables are tables that allow duplicate rows.
When FastLoad finds the duplicate rows it discards it. Fast
Load can load data into multiset table but will not load
the duplicate rows.
| Is This Answer Correct ? | 30 Yes | 3 No |
Answer / bharath
after you restart the fast load job,
Therefore, some number of rows will be sent to the AMPs
again because the restart starts on the next record after
the value stored in the checkpoint. Hence, when a restart
occurs, the first row after the checkpoint and some of the
consecutive rows are sent a second time. These will be
caught as duplicate rows after the sort. This restart logic
is the reason that FastLoad will not load duplicate rows
into a MULTISET table. It assumes they are duplicates
because of this logic.
| Is This Answer Correct ? | 13 Yes | 3 No |
Answer / tdguy
-->Fload does not support multiset tables because it does
not support duplicate rows.
-->Fload does not allow duplicate roww, because of the
restart logic.Whenever a failure occurs and restart occurs,
fload identifies the checkpoint and sends some records to
the amps which were already sent. This is because, failure
occurs at checkpoint rarely. Assume checkpoint is to be
taken every 10 rows and the failure occurs exactly while
processing at the 14th row. When Fload is restarted, it
identifies the checkpoint and sends the rows starting from
11th row. However the rows 11 to 14 will be captured as
duplicates and just counted. This can be seen in the stats
of Fload.
TOTAL DUPLICATE ROWS = 0
Though these rows are not captured, these rows are just
noted. This is the reason, Fload does not support duplicate
rows.
| Is This Answer Correct ? | 10 Yes | 2 No |
Answer / priyanka trivedi
restart logic is the reason that FastLoad will not load
duplicate rows into a MULTISET table
| Is This Answer Correct ? | 2 Yes | 1 No |
Answer / amit sethiya
I believe Fastload silently discards duplicate rows. They don't go to the error table.
Many of the differences between FastLoad and MultiLoad are due to the fact that MultiLoad loads by way of an intermediate work table, whereas Fastload loads directly into the target table, which is sorted later. The sorting process automatically removes duplicate rows. The records that MultiLoad loads the work table during the acquisition phase are not exact images of the target rows. They contain sequence numbers that are generated by the client module. If the acquisition phase is restarted, the client may resend rows that were previously sent after the last checkpoint, as is the case with Fastload. However, only duplicate records with matching sequence numbers are discarded when the work table is sorted at the end of the acquisition phase. Duplicate records with non-matching sequence numbers are retained.
| Is This Answer Correct ? | 1 Yes | 0 No |
Answer / hardeep
Thanks Priyanka for the answer but can u pls explain more about it. I didn't understand properly.
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / laks
fastload will rmove duplicates while loading ,But performence of the laod will degrade.
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / sharmistha meher
multiload uses checkpoint too, why this allows duplicates then?
| Is This Answer Correct ? | 0 Yes | 0 No |
Fast Load will load the Data Fastly,
Mean Concurrently,Bulk Insert.
Internally TeraData server will Create
Bulk insert DML statament
(Like: insert into Table1 as sel * from Table2
with data)
For Fast Performence it will not support the
duplicate values,Refential Intigrity,,,,
If u know the Better answer compare to this let me Know,
srinu.srinuvas@gmail.com
| Is This Answer Correct ? | 0 Yes | 15 No |
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