SELECT * from TWHERE ((KEY1 >='a' AND KEY1 <= 'b') OR (KEY1 > 'c' AND KEY1 <= 'e')) AND KEY2 IN (1, 2)

The List<List<KeyRange>> for SkipScanFilter for the above query would be [ [ [ a - b ], [ d - e ] ], [ 1, 2 ] ] where [ [ a - b ], [ d - e ] ] is the range for KEY1and [ 1, 2 ] keys for KEY2.