In most OBIA projects we create both incremental and full load mappings for each tables in Date Warehouse target. Below you can find the difference between both.
Full Load is the entire data dump load taking place the very first time. In this we give the last extract date as empty so that all the data gets loaded
Incremental - Where difference between target and source data is dumped at regular intervals.Here we give the last extract date such that only records after this date are loaded.
Note:
- Full load: $$Last_Extract_Date = either leave it blank or give some old date so that all the records are loaded
- Incremental load:$$Last_Extract_Date = The date from which you need the data (to get latest record).
- See more at: http://dwhlaureate.blogspot.jp/2012/06/what-is-full-load-incremental-load-full.html#sthash.Sn5gFBNo.dpuf
Note:
- Full load: $$Last_Extract_Date = either leave it blank or give some old date so that all the records are loaded
- Incremental load:$$Last_Extract_Date = The date from which you need the data (to get latest record).
- See more at: http://dwhlaureate.blogspot.jp/2012/06/what-is-full-load-incremental-load-full.html#sthash.Sn5gFBNo.dpuf
Note:
- Full load: $$Last_Extract_Date = either leave it blank or give some old date so that all the records are loaded
- Incremental load:$$Last_Extract_Date = The date from which you need the data (to get latest record).
- See more at: http://dwhlaureate.blogspot.jp/2012/06/what-is-full-load-incremental-load-full.html#sthash.Sn5gFBNo.dpuf
Note:
Full Load: Last_Extract_Date = either leave it blank or give some old date so that all the records are loaded.
Incremental Load: Last_Extract_Date = The date from which you need the data (to get latest record).
Why Incremental:
Speed.
Preserving history.
Full Load vs Incremental Load:
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Full Load
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Incremental Load
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Truncates all rows and loads from scratch.
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New records and updated ones are loaded
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Requires more time.
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Requires less time.
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Can easily be guaranteed
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Difficult. ETL must check for new/updated rows.
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Can be lost.
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Retained.
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