Databases Reference
In-Depth Information
Itemset_Key = 1 wherein all the other values are set to zero. Details of
this row will be provided in Chapter 7. For the purposes of this dis-
cussion, we can assume the Market Basket Table has been created and
populated.
mArket BAsket Query
Once a batch of Itemsets has been loaded into the Market Basket Table, the
data is ready to be queried into a usable form. The SQL that will perform this
query is in Figure 5.2. The indexing of the Market Basket Table, explained in
Chapter 6, makes the Market Basket Query feasible. The batch cycles of the
Market Basket Query, explained in Chapter 7, control the execution of the
Market Basket Query. The Market Basket Query selects data from only the
Market Basket Table in a recursive join that juxtaposes all the objects within
a single Itemset.
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fIGure 5.2
Market Basket Query.
