The PGD Builder is a command-line utility that builds a specialized index to improve performance of certain distance-based operations for native datasets containing lines and polygons. It can be downloaded from the Spectrum Spatial section of the Welcome Page, under PGD Builder on the Utilities tab.
A PGD index built for a TAB file is helpful when the data you're searching is based on lines or polygons and you are using:
- the Point in Polygon stage, when you are including distance
- the Find Nearest stage, when input is a point (whether or not you are including distance)
- SearchNearest operations in the Feature Service (with an input point and a line or polygons
search table)Note: A PGD file is 5-6 times larger than the .MAP file for the TAB. One PGD file is generated per TAB file, except in the case of a seamless TAB which will have PGD files created for each sub-TAB.
Also, a PGD file will no longer be used by the system if you change the data in the TAB (that is, if rows have been added or deleted or a geometry has been changed in the MAP portion of the TAB). If warnings are enabled (see Spatial Logging), a message about the out-of-date PGD file will appear in the spectrum-server.log or if applicable, in the log file that has been configured for Spatial logging. You must then regenerate the PGD for the updated TAB file.