GDS organizes keys with pointers or data to form records. A record has a header, which holds the record size, and a compression count, which identifies how much of the preceding key is held in common by this record. Records in the block are ordered by the values of their keys. The errors discussed in this section indicate damage to a record. Record errors present an added challenge, in that they potentially prevent GT.M from correctly interpreting subsequent records in the same block.

IF THE BLOCK IS A DATA BLOCK, that is, level zero (0), refer to section O3.

IF THE BLOCK IS AN INDEX BLOCK, that is, has a level greater than zero (0), the best option is generally to use the salvage strategy discussed in section O4. REMOVE the damaged record and INTEG the block. If the block is still corrupt, repeat the last step, REMOVE the pointer to it, and MAP it FREE. In any case, refer to section O4.