Calc/Proposal DataPilot byIBM
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Background
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Problem Description
Allocate a lot of abundant data For a simple datapilot table: Member A1 in L1 field will create a array for all members {B1,B2,B3}. But only B1 is visible and valid. Allocate too much memories Every member stored a big structure. Set too many border styles for output area Some borders are set twice or more.
Solution
Data Source buffer A document stored a source buffer array. Every table have a buffer id. The datapilot table can use the same id if they have same data source. In the buffer, the members of a field can be identified by an id( the sorted index ). Then in the output table's algorithm the ScDPItemData structure is replaced by an id. Only allocate visible member Enhancement of setting the border style