The load utilities for data warehouses have to deal with much
larger data volumes than for operational databases. There is
only a small time window (usually at night) when the
warehouse can be taken offline to refresh it. Sequential loads
can take a very long time, e.g., loading a terabyte of data can
take weeks and months! Hence, pipelined and partitioned
parallelism are typically exploited 6. Doing a full load has the
advantage that it can be treated as a long batch transaction
that builds up a new database. While it is in progress, the
current database can still support queries; when the load
transaction commits, the current database is replaced with the
new one. Using periodic checkpoints ensures that if a failure
occurs during the load, the process can restart from the last
checkpoint.
The load utilities for data warehouses have to deal with muchlarger data volumes than for operational databases. There isonly a small time window (usually at night) when thewarehouse can be taken offline to refresh it. Sequential loadscan take a very long time, e.g., loading a terabyte of data cantake weeks and months! Hence, pipelined and partitionedparallelism are typically exploited 6. Doing a full load has theadvantage that it can be treated as a long batch transactionthat builds up a new database. While it is in progress, thecurrent database can still support queries; when the loadtransaction commits, the current database is replaced with thenew one. Using periodic checkpoints ensures that if a failureoccurs during the load, the process can restart from the lastcheckpoint.
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Load the utilities for Data warehouses have much to Deal with
Data Volumes larger than for operational databases. There is
only a Small Window time (usually at Night) when the
Warehouse Can be taken offline to refresh it. Sequential loads
Can take a very long time, eg, a terabyte of Loading Data Can
take Months and weeks! Hence, pipelined and partitioned
parallelism are typically exploited 6. Doing a full Load has the
Advantage that Can it be treated As a long Batch Transaction
that builds up a New Database. While it is in Progress, the
current Database Support Can still queries; when the Load
Transaction commits, the current Database is replaced with the
New one. Using periodic checkpoints ensures that if a Failure
occurs during the Load, the Process Can restart from the last
Checkpoint.
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The load utilities for data warehouses have to deal with much
larger data volumes than for operational databases. There. Is
only a small time window (usually at night) when the
warehouse can be taken offline to refresh it. Sequential loads
can. Take a very, long time e.g, loading a terabyte of data can
take weeks and months! Hence pipelined and, partitioned
parallelism. Are typically exploited 6.Doing a full load has the
advantage that it can be treated as a long batch transaction
that builds up a new database. While. It is, in progress the
current database can still support queries; when the load
transaction commits the current, database. Is replaced with the
new one. Using periodic checkpoints ensures that if a failure
occurs during, the load the process can. Restart from the last
.Checkpoint.
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