transfer data

Hi, we are acquiring data  from systems on windows and  WindowsNT platform ,size of datafiles are in MB and
gigabytes(GB)My postgres database is installed on sun solaris platform.
 
 I would like to the know about the different methods or techniques  that i can apply to transfer the  data from these
systems(onwindows/NT) to my postgres (on Solaris platform)  database. All the systems (computer ) are well connected by
network.        
 

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