Hi, Matthieu, Before you go much further, it appears that recent versions of visual studio on windows have some serious problem with some header files, therefore, FastBit is not able to compile under windows using visual studio. However, you could use cygwin and mingw.
The dictionary in FastBit is assumed to be bi-directional. Given an integer code, it could look up a string, and given a string it could look up an integer code. Therefore, you might have trouble encoding the multi-level code the way you present it. FastBit allows you to use the name of a category as if it is the name of an integer column. In this regard, you could attempt to encode different categories into distinct ranges of values. Good Luck. John On 10/28/15 1:18 AM, Matthieu Bolt wrote: > All, > > I'm new to fastbit and investigating if I can use it for a windows 7 > 64bit desktop application. For now I'm using ardea to convert the data > to the required binary format. Most of my data are string values which > could be represented/stored by a unique integer value with use of some > dictionary. I understand from the documentation that the fastbit > library provides this functionality for category columns. However I > can't get ardea to create the dictionary files in the output directory > for category columns. > > - Can ardea be configured to create the dictionary files for category > columns? > - Are category columns represented with strings or integer values in > the binary format (if a dictionary file is not created)? > - What happens if a category value doesn't occur in the user supplied > dictionary or the user supplied dictionary file doesn't exist at all. > > - Is it be possible to query the category data using a range of > integer values (that represent the category values)? > The reason that I ask this is that for this application it makes sense > to group the category values together (on many levels for most > columns) and I hope to use an ordered integer representation to > improve the performance of querying those category values (see example > below) while not storing additional grouping information for all > category values for all records. The grouping/levels logic would then > be implemented in the application logic (preferably by using the > fastbit dictionary. > > Best regards, > > Matthieu > > > Example of grouping of category values: > IntegerRepresentation,Value, Level0, Level1,Level2,etc > 1,Jimmy'sBoa,BoaConstrictor,Snake,Reptile > 2,Kaa,BoaConstrictor,Snake,Reptile > 3,Nagini,Python,Snake,Reptile > 4,Winnie-the-Pooh,BrownBear,Bear,Mammal. > 5,Baloo,BrownBear,Bear,Mammal > > Example of query: > All Snakes would translate to Value>0 and Value <4 > instead of Value==Jimmy'sBoa or Value==Kaa or Value==Nagini > > > > > > _______________________________________________ > FastBit-users mailing list > [email protected] > https://hpcrdm.lbl.gov/cgi-bin/mailman/listinfo/fastbit-users > _______________________________________________ FastBit-users mailing list [email protected] https://hpcrdm.lbl.gov/cgi-bin/mailman/listinfo/fastbit-users
