1  –  Total transactions field

    This field gives the total number of transactions that have been
    committed or rolled back, including read-only transactions.

2  –  R O transactions field

    This field gives the total number of read-only transactions that
    have been committed or rolled back.

3  –  retrieved_record_field

    This field gives the number of records retrieved by read-only
    transactions.

4  –  __fetched_line_field

    This field gives the number of lines fetched by read-only
    transactions. To retrieve a single record, a transaction might
    actually check a number of lines, some of which may be empty.

5  –  ____read_snap_page_field_

    This field gives the number of snapshot pages fetched by read-
    only transactions. If this count is high relative to the other
    read fields, read-only transactions are fetching records that
    are being updated frequently, and the snapshot file is being used
    extensively.

6  –  stored_snap_record_field

    This field gives the number of records stored in the snapshot
    file by update transactions. Every snapshot record stored by an
    update transaction implies that a snapshot page was found and
    utilized. In the best case, this is a single-page fetch. The
    "page in use," "page too full," page conflict," and "extended
    file" subfields indicate some of the extra overhead involved
    in finding suitable snapshot pages on which to store snapshot
    records.

7  –  ____page_in_use_field_

    This field gives the number of pages fetched that were unsuitable
    for storing snapshot records because the page was owned by
    another transaction. A new snapshot page cannot be used again
    until the TSN that denotes the age of the page is less than the
    oldest active TSN in the database. This ensures that read-only
    transactions always find the correct version of a record.

8  –  ____page_too_full_field_

    This field gives the number of pages fetched that were unsuitable
    for storing snapshot records because there was not enough room on
    the snapshot page to include another version of a record. In this
    case, a new snapshot page must be fetched and linked with the
    full page. This allows read-only transactions to follow a chain
    of snapshot pages to find the correct version of a record.

9  –  ____page_conflict_field_

    This field gives the number of times a snapshot page fetch
    was requested but aborted due to a lock conflict with another
    process. When a page fetch conflicts with another process,
    another target page is fetched and checked so the lock conflict
    does not cost a disk I/O operation.

10  –  ____extended_file_field_

    This field gives the number of times the snapshot file has been
    extended. The snapshot file is extended when an update operation
    cannot find a suitable page on which to store a snapshot record
    after checking a certain number of pages.