Subset Database

Use the Database > Export > Subset GDB or the Database Tools > Window Data > Subset Database menu options, (DBSUBSET GX), to create a subset database from the current database.

Subset Database dialog options

Subset database	The name of the new subset database to create Script Parameter: DBSUBSET.NAME
Lines	"Selected" to only copy selected lines. "All" to copy all lines. Script Parameter: DBSUBSET.LINES
Channels	"Displayed" to only copy currently displayed channels. "All" to copy all channels. Script Parameter: DBSUBSET.CHANNELS
Remove mask dummies	"No masking" to subset the data including all data. "Leading/Trailing" removes only leading and trailing dummies. "All dummies" will remove all dummies. If "Leading/Trailing" or "All dummies" is selected, a mask channel must be specified and masking will take place based on the dummies in the mask channel. Note that "Leading/Trailing" masking is much faster than "All dummies". Script Parameter: DBSUBSET.DUMMY
Mask channel	The optional name of a mask channel to use as a dummy mask. Elements that are dummied in the mask channel will not be placed in the subset database according to the dummy mask option specified by the previous prompt. If a mask channel is not specified, all data in each channel will be copied to the subset database. Script Parameter: DBSUBSET.MASK
Compression type	Type of compression to use in the database: None (No compression of any kind) Speed (Compress with database performance in mind. This is usually faster than No compression). Size (Compress with database size in mind. This will achieve the smallest database size. Script Parameter: DBSUBSET.COMPRESSION

Application Notes

To create a subset database using a mask requires that a mask channel be defined such that the unwanted data is dummied out in the mask. For example, the data windowing functions can be used to window the X and Y channels based on a defined polygonal mask, and the "X" channel can then be used as the mask channel.