METHOD AND SYSTEM FOR MODIFICATION OF AN UNLOCKED RECORD OF A DATABASE BY INTERACTING PROCESSES

• US 20090271446A1
• Filed: 04/27/2009
• Published: 10/29/2009
• Est. Priority Date: 04/25/2008
• Status: Abandoned Application

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Depreter, Frederic
• Application Number:
  US12/430,391
• Publication Number:
  US 20090271446A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/2343 Locking methods, e.g. distributed locking or locking implementation details
• CPC Class Codes: G06F 9/526 Mutual exclusion algorithms

Abstract

In a method for modifying an unlocked record of a database by interacting processes, a first process accesses the record and locks it, then checks if the record is marked for post-processing. In case the record is not marked for post-processing the first process proceeds to the following actions: performs the operations on the record, unlocks the record and terminates. In case the record is marked for post-processing the first process performs the following steps: sets the flag to a predefined first state which denotes that post-processing is due, performs the operations to the record and saves them, unlocks the record, calls a second process and terminates. In the case that the record is marked for post-processing, the second process performs the following steps: performs further operations to the record and saves them, sets the flag to a predefined second state which denotes that post-processing is done and terminates.

Claims

1. A method for modifying an unlocked record of a database by interacting processes, which comprises the steps of:

a) performing a first process which accesses a record and locks the record in order to perform operations to the record;

b) checking during the first process if the record is marked for post-processing by detecting a presence of a flag in the record;

c) performing, via the first process, the following actions in a case the record is not marked for post-processing and thus a presence of the flag is lacking;

performing the operations on the record;

unlocking the record and terminating the first process;

d) performing, via the first process, the following steps in a case the record is marked for post-processing and thus a presence of the flag is detected;

setting the flag to a predefined first state which denotes that post-processing is due;

performing the operations to the record and saves the record;

unlocking the record;

calling a second process and terminating the first process;

e) performing, via the second process, the following steps in a case where the record is marked for post-processing;

performing further operations to the record and saving the record; and

setting the flag to a predefined second state which denotes that the post-processing is done and terminating the second process.

2. The method according to claim 1, wherein the first process is a foreground process and the second process is a background process.

3. The method according to claim 1, wherein the predefined first state of the flag is equivalent to a lock state of the record, preventing an access to the record by any arbitrary process other than the second process and the predefined second state of the flag is equivalent to an unlocked state of the record, granting access to the record by any arbitrary process.

4. The method according to claim 3, wherein the second process is granted access to the record, the record containing the flag set to the predefined first state, by either being called from within the first process or by inheriting access rights to the record by means of interprocess communication.

5. The method according to claim 1, which further comprises, applying, via the first process, a change to the flag based on identifying a necessity of calling the second process.

6. A module, comprising:

software code adapted to be used as a plug-in, the plug-in being importable into database software systems, the software code performing a method for modifying an unlocked record of a database by interacting processes, the software code performing the steps of;

a) performing a first process which accesses a record and locks the record in order to perform operations to the record;

b) checking during the first process if the record is marked for post-processing by detecting a presence of a flag in the record;

c) performing, via the first process, the following actions in a case the record is not marked for post-processing and thus a presence of the flag is lacking;

performing the operations on the record;

unlocking the record and terminating the first process;

d) performing, via the first process, the following steps in a case the record is marked for post-processing and thus a presence of the flag is detected;

setting the flag to a predefined first state which denotes that post-processing is due;

performing the operations to the record and saves the record;

unlocking the record;

calling a second process and terminating the first process;

e) performing, via the second process, the following steps in a case where the record is marked for post-processing;

performing further operations to the record and saving the record; and

setting the flag to a predefined second state which denotes that the post-processing is done and terminating the second process.

7. A module, comprising:

a software library, the software library being adapted to be included into a code base of database software systems, the software library performing a method for modifying an unlocked record of a database by interacting processes, the software library performing the steps of;

a) performing a first process which accesses a record and locks the record in order to perform operations to the record;

b) checking during the first process if the record is marked for post-processing by detecting a presence of a flag in the record;

c) performing, via the first process, the following actions in a case the record is not marked for post-processing and thus a presence of the flag is lacking;

performing the operations on the record;

unlocking the record and terminating the first process;

d) performing, via the first process, the following steps in a case the record is marked for post-processing and thus a presence of the flag is detected;

setting the flag to a predefined first state which denotes that post-processing is due;

performing the operations to the record and saves the record;

unlocking the record;

calling a second process and terminating the first process;

e) performing, via the second process, the following steps in a case where the record is marked for post-processing;

performing further operations to the record and saving the record; and

setting the flag to a predefined second state which denotes that the post-processing is done and terminating the second process.