Hi Kohei, On Thursday, 2013-03-14 09:26:55 -0400, Kohei Yoshida wrote:
I believe the same functionality can be achieve via database connectivity, by having such external data provider register as a database, and use it to act as a data provider for pivot tables. So, I don't see a reason why we need to keep this as a separate data source category.IMHO the advantage of the data provider is that the actual data does not have to reside in the spreadsheet, allowing for massive amounts of data records but providing only the information necessary for the pivot table. This maybe could be accomplished as well using a registered data source, but currently we have no means to pull the data without actually storing it in the spreadsheet for further processing. Or isn't that the case?Well, that would depend on what you actually mean by "storing (the data) in the spreadsheet". When pulling data via database connectivity, we don't actually copy the data in the spreadsheet document, but generate the pivot table output directly from it. But we *do* first populate the pivot cache from the database internally, so a copy of the data will sit in memory while the document is open.
That's my bad then. I assumed the data was stored in a DB range. Is that different with the data provider, i.e. does it not need to copy all data to populate the pivot cache with an interface to directly populate the layouted pivot table? Other advantages a data provider could have are a) be able to collect data from various e.g. remote sources that a simple data connection could not provide, and b) access data in means not possible with database connectivity, for example if the user shall be restricted to a subset of a database or not be able to query using SQL statements. Probably there'll always be _some_ use cases such a provider could have (does Excel have that? if yes then there are ...), so if it's ripped out maybe offering a new interface adapted to the new data types and structures that sits on top of the engine instead of being part of it would be good. Eike -- LibreOffice Calc developer. Number formatter stricken i18n transpositionizer. New GnuPG key 0x65632D3A : 2265 D7F3 A7B0 95CC 3918 630B 6A6C D5B7 6563 2D3A Old GnuPG key 0x293C05FD : 997A 4C60 CE41 0149 0DB3 9E96 2F1A D073 293C 05FD Support the FSFE, care about Free Software! https://fsfe.org/support/?erack
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