索引节点导出的块头信息解释

rdba - relative database block address of the branch block (file no/block no)
scn – system change number of the block when last changed
seq – number of block changes
type – block type
seg/obj – object id
typ – segment type (index)
Itl – Interested transaction Slots (default 2 for leaf blocks) including slot id,
transaction id, undo block address, flag and locking info and scn of transaction

kdxcolev: index level (0 represents leaf blocks)
kdxcolok: denotes whether structural block transaction is occurring
kdxcoopc: internal operation code
kdxconco: index column count
kdxcosdc: count of index structural changes involving block
kdxconro: number of index entries (does not include kdxbrlmc pointer)
kdxcofbo: offset to beginning of free space within block
kdxcofeo: offset to the end of free space (ie. first portion of block containing index data)
kdxcoavs: available space in block (effectively area between the two fields above)

kdxbrlmc: block address if index value is less than the first (row#0) value
kdxbrsno: last index entry to be modified
kdxbrbksz: size of usable block space

kdxlespl: bytes of uncommitted data at time of block split that have been cleaned out
kdxlende: number of deleted entries
kdxlenxt: pointer to the next leaf block in the index structure via corresponding rba
kdxleprv: pointer to the previous leaf block in the index structure via corresponding rba
kdxlebksz: usable block space (by default less than branch due to the additional ITL entry)

Row number (starting at 0) [starting location in block] dba
Column number followed by column length followed by column value
Repeated for each indexed index
Repeated for each branch entry
Note: column value is abbreviated to smallest value that uniquely
defines path

row number (starting at 0) followed by [starting location within block]
followed by various flags (locking information, deletion flag etc.)
index column number (starting at 0) followed by column length
followed by column value
repeated for each indexed column
repeated for each index entry

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