x3236" name="idx3236">It holds share-mode locks and update locks (which have not yet been upgraded to exclusive locks) until one of the following events occurs:
  • It holds exclusive locks until the end of the transaction even if you close the smart large object.

    • When one of the preceding conditions occurs, the smart-large-object optimizer releases the lock on the smart large object.

    Important:
    You lose the lock at the end of a transaction even if the smart large object remains open. When the smart-large-object optimizer detects that a smart large object has no active lock, it automatically obtains a new lock when the first access occurs to the smart large object. The lock that it obtains is based on the original access mode of the smart large object.

    The smart-large-object optimizer releases the lock when the current transaction terminates. However, the optimizer obtains the lock again when the next function that needs a lock executes. If this behavior is undesirable, use BEGIN WORK transaction blocks and place a COMMIT WORK or ROLLBACK WORK statement after the last statement that needs to use the lock.

    Status Information

    Table 27 shows the status information that the database server maintains for a smart large object.

    Table 27. Status Information for a Smart Large Object
    Status Information Description
    Last-access time The time, in seconds, that the smart large object was last accessed

    This value is available only if the last-access time attribute is enabled for the smart large object.
    Storage characteristics The storage characteristics for the smart large object
    Last-change time The time, in seconds, of the last change in status for the smart large object

    A change in status includes changes to metadata and user data (data updates and changes to the number of references). This system time is stored as number of seconds since January 1, 1970.
    Last-modification time The time, in seconds, that the smart large object was last modified

    A modification includes only changes to user data (data updates). This system time is stored as number of seconds since January 1, 1970.

    On some platforms, the last-modification time might also have a microseconds component, which can be obtained separately from the seconds component.
    Reference count The number of references (LO handles) to the smart large object
    Size The size, in bytes, of the smart large object

    The database server stores the status information in the metadata area of the sbspace.

    Tip:
    The time values (such as last-access time and last-change time) might differ slightly from the system time. This difference is due to the algorithm that the database server uses to obtain the time from the operating system.

    For more information on how to obtain status information in a DataBlade API module, see Obtaining Status Information for a Smart Large Object.

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