github.com/cockroachdb/pebble@v1.1.2/internal/keyspan/testdata/fragmenter_values (about)

     1  build
     2  3: a-----------m              apples
     3  2:      f------------s        bananas
     4  1:          j---------------z coconuts
     5  ----
     6  3: a----f                     apples
     7  3:      f---j                 apples
     8  2:      f---j                 bananas
     9  3:          j--m              apples
    10  2:          j--m              bananas
    11  1:          j--m              coconuts
    12  2:             m-----s        bananas
    13  1:             m-----s        coconuts
    14  1:                   s------z coconuts
    15  
    16  # Building is idempotent.
    17  build
    18  3: a----f                     a
    19  3:      f---j                 b
    20  2:      f---j                 c
    21  3:          j--m              d
    22  2:          j--m              e
    23  1:          j--m              f
    24  2:             m-----s        g
    25  1:             m-----s        h
    26  1:                   s------z i
    27  ----
    28  3: a----f                     a
    29  3:      f---j                 b
    30  2:      f---j                 c
    31  3:          j--m              d
    32  2:          j--m              e
    33  1:          j--m              f
    34  2:             m-----s        g
    35  1:             m-----s        h
    36  1:                   s------z i
    37  
    38  build
    39  2: a--c                       apple
    40  1:  b--d                      banana
    41  truncate-and-flush-to c
    42  ----
    43  2: ab                         apple
    44  2:  bc                        apple
    45  1:  bc                        banana
    46  1:   cd                       banana
    47  
    48  build
    49  3: a-c                        apple
    50  2: a---e                      banana
    51  1: a-----g                    coconut
    52  truncate-and-flush-to d
    53  3:    d----i                  orange
    54  ----
    55  3: a-c                        apple
    56  2: a-c                        banana
    57  1: a-c                        coconut
    58  2:   cd                       banana
    59  1:   cd                       coconut
    60  3:    de                      orange
    61  2:    de                      banana
    62  1:    de                      coconut
    63  3:     e-g                    orange
    64  1:     e-g                    coconut
    65  3:       g-i                  orange