Watch the Example 5 online guitar lesson by Brad Carlton from Guitar Lab: Boogie-Woogie
This example is a four voice passage. The chords are: A, D/A, A7(no3rd) then back to D/A. The 1st voice moves 3, 4, 5, 4; the 2nd voice pedals the root; the 3rd voice moves 5, 6, b7, 6 and the 4th voice pedals the root. A mixolydian is the source for these chords. Study the video closely to absorb the different picking hand options. By juggling the notes around, you can create many variations of this common boogie-woogie pattern.