H_I>Within a block, records are stored in ascending sequence. The block header contains the offset of the last record in the block. When a record is deleted, any records that follow it "move up" to overwrite it and the record length is subtracted from the last record offset in the block header.
H_I>...
H_I>If a record is deleted, records after it move up in the block and the record length is subtracted from the last record offset in the block header.
H_I>...

H_I>For example, in the sample structure each level 1 index record contains 10. Each level 2 record contains 100. Each level 3 record contains 1000.

H_I>If the record with key = 128 is deleted, then the level 1 record with key 121 contains 9. The level 2 record with key 101 contains 99. The level 3 index with key 1 contains 999.