Hi Augustin,
you can configure this parameter within the Spatial Manager in Spectrum.
Go to
http://spectrum_host:8080/SpatialServerManagerLogin as an admin.
In the banner go to Services=>Feature
Here you will be able to increase the maximum of features returned.
If you mean with 'maximum of fields' the number of columns that a layer can contain, I doubt there is a limit. Nevertheless the tab file itself has a limit. There isn't a hard limit for databases. Just bandwidth, memory and processing power.
Regards
Andreas
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Andreas Homa
PITNEY BOWES SOFTWARE, INC
Troy NY
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