[postgis-users] masking out part of a MULTILINESTRING

[Purvis, Charlton]

Apologies ahead of time if this is a bone headed Q, but I can't get my hands
around the function that holds the keys to the kingdom.

Say that I have one MULTILINESTRING that contains these vertices:
  (0,0)
  (1,0)
  (2,0)
  (3,0)
  (4,0)
  (5,0)

Now say that I want to mask out the BBOX that is defined by:
  (1,-1) to (2,1)

How can I clip the MULTILINESTRING to show me only those lines that are
outside the BBOX?  If I do a
  not geom. && BBOX...,
it kills the whole MULTILINESTRING since part of the MULTILINESTRING is
inside the BBOX.  And that's not what I want.

I want to end up w/ an image or geom. that has these segments:
  (0,0) to (0,1)
  (2,0) to (5,0)

Any ideas?

Thanks,

Charlton
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