In ur current projectu have done any performance tuning of
mappings?
Answer / sreedhar lokaray
Many people are not sure how exactly to tune the
performance of a mapping. There is no thumb rule for
performance tuning. A tuning done in one mapping cannot be
applied into another mapping. But still below given are
some of the performance tuning tips.
Joiner instead of Lookup: If the lookup table has large no.
of records then the performance will affect because it has
to build the cache. Instead use a joiner transformation and
check it as detail rows. This will avoid building cache.
Sorted Input: Use sorter transformation before joiner or
aggregator. This will improve the performance.
Source Qualifier: Try to filter out unwanted records in the
source qualifier before moving to the next transformation.
Also delete unconnected/unused ports.
Indexes: Try to have proper indexes on the required fields
of the tables in the database which will increase the
performance. At the same time having indexes on the target
will kill the performance when you try to insert huge
volumes of data. To avoid this, disable the indexes on the
target (using sql loader direct load process) and then load
the data. After loading enable the index back.
Keep in mind that tuning performance of one transformation
can kill the performance of other transformation. We have
to maintain the equilibrium.
| Is This Answer Correct ? | 8 Yes | 0 No |
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