Asynchronous transcription object management system

• US 7,206,805 B1
• Filed: 11/17/2000
• Issued: 04/17/2007
• Est. Priority Date: 09/09/1999
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: McLaughlin, Michael James Jr.
• Primary Examiner(s): Follansbee; John
• Assistant Examiner(s): Nguyen; Dustin
• Application Number:
  US09/715,955
• Time in Patent Office: 2,342 Days
• Field of Search: 709/238, 709/235, 709/201, 709/203, 707/10, 707/103, 707/202, 714/4, 714/15, 718/101
• US Class Current: 709/203
• CPC Class Codes: G06F 9/466 Transaction processing
• CPC Class Codes: Y10S 707/99953 Recoverability

Abstract

Described herein is a system for executing distributed transactions. A coordinator and one or more participants cooperate to execute a distributed transaction, the distributed transaction including for each participant a transaction executed by the participant. To manage the transaction, the coordinator and the participant communicate over a network using, for example, a stateless protocol. Before each participant commits the transaction, the participants determine that the coordinator has committed the transaction. The coordinator commits the transaction after receiving acknowledgment from all the participants that they will commit the transaction. To determine whether the coordinator has committed the transaction, a participant transmits a message to the coordinator to acknowledge that it will commit the distributed transaction. The participant commits its respective transaction if it receives an acknowledgement from the coordinator. For the particular transaction being executed by a participant, the participant prevents other transactions from modifying a data item affected by the particular transaction. The participant will prevent such modifications until termination criteria for the particular transaction is satisfied, in which case the participant terminates the transaction.

Claims

1. A method of managing execution of a distributed transaction that includes one or more transactions, each of said one or more transactions being executed by a respective participant of one or more participants participating in said distributed transaction, the method comprising the steps of:

a first participant receiving from a coordinator of said distributed transaction a request for a vote of whether to commit said distributed transaction, said first participant executing a first transaction of said one or more transactions;

in response to receiving said request for a vote, said first participant transmitting to said coordinator a message specifying that said first participant votes to commit;

after said first participant transmitting to said coordinator a message specifying that said participant votes to commit, said first participant receiving from said coordinator a request to commit the first transaction;

in response to receiving said request to commit and before said first participant commits said first transaction, said first participant transmitting a request to said coordinator for said coordinator to acknowledge that said coordinator has committed said distributed transaction; and

if said coordinator acknowledges that said coordinator has committed said distributed transaction, then said first participant committing said first transaction.

2. The method of claim 1, wherein said coordinator commits said distributed transaction when each participant of said one or more participants acknowledges that the respective transaction of said each participant will be committed by said each participant.

3. The method of claim 1, wherein said coordinator and said first participant cooperate to execute the distributed transaction by transmitting messages to each other over a network.

4. The method of claim 3, wherein the step of said first participant receiving a request to commit a first transaction includes receiving a request transmitted over said network to said first participant.

5. The method of claim 4, wherein said network is the Internet.

6. The method of claim 3, wherein said first participant receives said request as a message transmitted over a network using a stateless protocol.

7. The method of claim 6, wherein said stateless protocol is HTTP or HTTPS.

8. The method of claim 1, further including the step of said first participant aborting said first transaction when said coordinator has not acknowledged committing said distributed transaction.

9. The method of claim 1, wherein:

said first transaction includes a first modification to an object;

the method includes said first participant receiving a request to execute a second transaction, wherein said second transaction includes a second modification of said object;

said first participant determining whether said first transaction satisfies termination criteria before allowing said second modification to said object.

10. The method of claim 9, wherein said termination criteria includes one or more criteria for aborting said first transaction that are based on a transaction quantum value that indicates a period of time between transmitting a message to said first participant and receiving an acknowledgement that said request has been processed;

wherein the step of determining whether said first transaction satisfies termination criteria includes determining whether said first transaction satisfies said one or more criteria; and

if said first transaction satisfies said one or more criteria, then aborting said first transaction.

11. The method of claim 9, wherein:

said object is a database table associated with a trigger executed before modifying a row on said database table; and

the step of determining is performed while executing said database trigger.

12. A method of managing the execution of a distributed transaction that includes one or more transactions, each of said one or more transactions being executed by a respective participant of a plurality of participants participating in said distributed transaction, the method comprising the steps of:

a coordinator of said distributed transaction transmitting to a first participant a request for a vote of whether to commit said distributed transaction, said first participant executing a first transaction of said one or more transactions;

said coordinator receiving from said first participant, as a response to said request for a vote, a message that specifies that said first participant votes to commit;

after said coordinator receiving from said first participant a message that specifies that said first participant votes to commit;

said coordinator transmitting to said first participant a first request to commit said first transaction,

said coordinator transmitting to a second participant in said distributed transaction a second request to commit a second transaction of said one or more transactions;

wherein said coordinator transmits said first request and said second request via a network using a stateless protocol;

after said coordinator transmits said first request and said second request, said coordinator committing said distributed transaction;

after said coordinator committing said distributed transaction, said coordinator receives a request from said first participant to acknowledge whether said coordinator has committed said distributed transaction;

in response to said coordinator receiving a request from said first participant to acknowledge whether said coordinator has committed said distributed transaction, said coordinator transmitting a message to said first participant to indicate that said coordinator has committed the distributed transaction; and

said coordinator transmitting a message to said second participant to indicate that said coordinator has committed the distributed transaction.

13. The method of claim 12, wherein:

the method further includes the step of determining that said first participant and said second participant are commencing committing of said first transaction and said second transaction respectively; and

the step of said coordinator committing said distributed transaction occurs in response to said coordinator determining that said first participant and said second participant are commencing committing of said first transaction and said second transaction respectively.

14. The method of claim 13, wherein the step of determining that said first participant and said second participant are commencing is performed by determining that:

said first participant has acknowledged receiving said first request, and

said second participant has acknowledged receiving said second request.

15. A computer-readable storage medium carrying one or more sequences of instructions for managing execution of a distributed transaction that includes one or more transactions, each of said one or more transactions being executed by a respective participant of one or more participants participating in said distributed transaction, wherein execution of the one or more sequences of instructions by one or more processors causes the one or more processors to perform the steps of:

a first participant receiving from a coordinator of said distributed transaction a request for a vote of whether to commit said distributed transaction, said first participant executing a first transaction of said one or more transactions;

in response to receiving said request for a vote, said first participant transmitting to said coordinator a message specifying that said first participant votes to commit;

after said first participant transmitting to said coordinator a message specifying that said participant votes to commit, said first participant receiving from said coordinator a request to commit the first transaction;

in response to receiving said request to commit and before said first participant commits said first transaction, said first participant transmitting a request to said coordinator for said coordinator to acknowledge that said coordinator has committed said distributed transaction; and

if said coordinator acknowledges that said coordinator has committed said distributed transaction, then said first participant committing said first transaction.

17. The computer-readable storage medium of claim 15, wherein said coordinator commits said distributed transaction when each participant of said one or more participants acknowledges that the respective transaction of said each participant will be committed by said each participant.

18. The computer-readable storage medium of claim 15, wherein said coordinator and said first participant cooperate to execute the distributed transaction by transmitting messages to each other over a network.

19. The computer-readable storage medium of claim 18, wherein the step of said first participant receiving a request to commit a first transaction includes receiving a request transmitted over said network to said first participant.

20. The computer-readable storage medium of claim 19, wherein said network is the Internet.

21. The computer-readable storage medium of claim 18, wherein said first participant receives said request as a message transmitted over a network using a stateless protocol.

22. The computer-readable storage medium of claim 21, wherein said stateless protocol is HTTP or HTTPS.

23. The computer-readable storage medium of claim 15, further including the step of said first participant aborting said first transaction when said coordinator has not acknowledged committing said distributed transaction.

24. The computer-readable storage medium of claim 15, wherein:

said first transaction includes a first modification to an object;

the steps include said first participant receiving a request to execute a second transaction, wherein said second transaction includes a second modification of said object;

said first participant determining whether said first transaction satisfies termination criteria before allowing said second modification to said object.

25. The computer-readable storage medium of claim 24, wherein said termination criteria includes one or more criteria for aborting said first transaction that are based on a transaction quantum value that indicates a period of time between transmitting a message to said first participant and receiving an acknowledgement that said request has been processed;

wherein the step of determining whether said first transaction satisfies termination criteria includes determining whether said first transaction satisfies said one or more criteria; and

if said first transaction satisfies said one or more criteria, then aborting said first transaction.

26. The computer-readable storage medium of claim 24, wherein:

said object is a database table associated with a trigger executed before modifying a row on said database table; and

the step of determining is performed while executing said database trigger.

16. A computer-readable storage medium carrying one or more sequences of instructions for managing the execution of a distributed transaction that includes one or more transactions, each of said one or more transactions being executed by a respective participant of a plurality of participants participating in said distributed transaction, wherein execution of the one or more sequences of instructions by one or more processors causes the one or more processors to perform the steps of:

a coordinator of said distributed transaction transmitting to a first participant a request for a vote of whether to commit said distributed transaction, said first participant executing a first transaction of said one or more transactions;

said coordinator receiving from said first participant, as a response to said request for a vote, a message that specifies that said first participant votes to commit;

after said coordinator receiving from said first participant a message that specifies that said first participant votes to commit;

said coordinator transmitting to said first participant a first request to commit said first transaction,

said coordinator transmitting to a second participant in said distributed transaction a second request to commit a second transaction of said one or more transactions;

wherein said coordinator transmits said first request and said second request via a network using a stateless protocol;

after said coordinator transmits said first request and said second request, said coordinator committing said distributed transaction;

after said coordinator committing said distributed transaction, said coordinator receives a request from said first participant to acknowledge whether said coordinator has committed said distributed transaction;

in response to said coordinator receiving a request from said first participant to acknowledge whether said coordinator has committed said distributed transaction, said coordinator transmitting a message to said first participant to indicate that said coordinator has committed the distributed transaction; and

said coordinator transmitting a message to said second participant to indicate that said coordinator has committed the distributed transaction.

27. The computer-readable storage medium of claim 16, wherein:

the steps include the step of determining that said first participant and said second participant are commencing committing of said first transaction and said second transaction respectively; and

the step of said coordinator committing said distributed transaction occurs in response to said coordinator determining that said first participant and said second participant are commencing committing of said first transaction and said second transaction respectively.

28. The computer-readable storage medium of claim 27, wherein the step of determining that said first participant and said second participant are commencing is performed by determining that:

said first participant has acknowledged receiving said first request, and

said second participant has acknowledged receiving said second request.