Data Blocks  «Prev

Segment_header_block in Oracle

Oracle Data Block consisting of 1) data block header, 2) table directory, 3) row directory 4) free space 5) row data

  1. data block header: references information about the data block header
  2. table directory: references information about the tables which have rows in this block
  3. row directory: references information about actual rows, including an address for each row.
  4. free space: references information about the free space allocated for INSERT and UPDATE; actual use of free space depends on the value of
  5. PCTFREE row data: references information about table data and index data