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Ntext
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Nvarchar(max)
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Default Behavior
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Data is stored as a LOB
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Stores data in-row
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Data is stored
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Out of the data page as
LOB
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Stored data In-Row ( if less than 4000)
Stored as LOB ( when more than 4000)
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Read-aHead Reads
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All the rows are read-ahead every time. Does not seems to depend on the cache
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Didn’t read-ahead during the testing
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Elapse time to insert 200 records
Ex insert into testTable1 select REPLICATE('ABBD455',2000)
go 200
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High
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Low
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The last few months it’s all been dbt. Dbt is a transform and load tool which is provided by fishtown analytics. For those that have created incremental models in dbt would have found the simplicity and easiness of how it drives the workload. Depending on the target datastore, the incremental model workload implementation changes. But all that said, the question is, should the incremental model use high-watermark as part of the implementation. How incremental models work behind the scenes is the best place to start this investigation. And when it’s not obvious, the next best place is to investigate the log after an test incremental model execution and find the implementation. Following are the internal steps followed for a datastore that does not support the merge statements. This was observed in the dbt log. - As the first step, It will copy all the data to a temp table generated from the incremental execution. - It will then delete all the data from the base table th
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