Mechanism for communication in a distributed database

Patent metadata

Field	Value
Publication number	US-2016267121-A1
Application number	US-201615159210-A
Country	US
Kind code	A1
Filing date	May 19, 2016
Priority date	Oct 21, 2013
Publication date	Sep 15, 2016
Grant date	—

Abstract

In a method for providing communication integrity within a distributed database computer system, a first node of a plurality of nodes transmits a change notification to a second node of the plurality of nodes. The change notification indicates that the first node has changed from a first version to a second version. The first node receives at least one change confirmation from the second node. The change confirmation confirms acknowledgment of the change notification by the second node and by a third node of the plurality of nodes. The first node updates a version table of the first node to show that the second node and the third node know that the first node has changed from the first version to the second version.

First claim

What is claimed is:

1 . A method for providing communication integrity within a distributed database computer system, the method comprising the steps of:
transmitting, by a first node of a plurality of nodes, a change notification to a second node of the plurality of nodes, wherein the change notification indicates that the first node has changed from a first version to a second version; receiving, by the first node of the plurality of nodes, at least one change confirmation from the second node, the change confirmation confirming acknowledgment of the change notification by the second node and by a third node of the plurality of nodes; and updating, by the first node of the plurality of nodes, a version table of the first node to show that the second node and the third node know that the first node has changed from the first version to the second version, wherein the version table of the first node shows the first node's knowledge about what the second node knows about the version of the first node and a version of the third node, and about what the third node knows about the version of the first node and a version of the second node.

2 . The method of claim 1 , wherein the step of receiving, by the first node of the plurality of nodes, at least one change confirmation from the second node includes receiving a change confirmation from each node of the plurality of nodes.

3 . The method of claim 1 , wherein the change confirmation confirming acknowledgment of the change notification by the second node and by the third node comprises a notification that the second node and the third node know that the first node has changed from the first version to the second version.

4 . The method of claim 1 , wherein:
the plurality of nodes includes at least four nodes; and the version table of the first node shows the first node's knowledge about what each of the nodes in the plurality of nodes knows about versions of each of the other nodes in the plurality of nodes.

5 . The method of claim 1 , further comprising:
receiving, by the first node of the plurality of nodes, a change notification from the second node, wherein the change notification indicates that the second node has changed from a first version to a second version; and transmitting, by the first node of the plurality of nodes, a change confirmation to the second node, the change confirmation confirming acknowledgement of the received change notification.

6 . The method of claim 5 , further comprising:
updating, by the first node of the plurality of nodes, an attribute table of the first node to show that the second node has changed from the first version to the second version.

7 . The method of claim 6 , further comprising:
updating, by the first node of the plurality of nodes, the version table of the first node to show that the second node knows that the second node has changed from the first version to the second version.

8 . The method of claim 1 , further comprising:
receiving, by the first node of the plurality of nodes, a change notification of the third node from the second node, wherein the change notification indicates that the third node has changed from a first version to a second version; and transmitting, by the first node of the plurality of nodes, a change confirmation to the second node for transmission to the third node, the change confirmation confirming acknowledgement of the received change notification.

9 . The method of claim 8 , further comprising:
updating, by the first node of the plurality of nodes, an attribute table of the first node to show that the third node has changed from the first version to the second version.

10 . The method of claim 9 , further comprising:
updating, by the first node of the plurality of nodes, the version table of the first node to show that the second node and the third node know that the third node has changed from the first version to the second version.

11 . A computer program product for providing communication integrity within a distributed database computer system, the computer program product comprising:
one or more computer-readable storage media and program instructions stored on the one or more computer-readable storage media, the program instructions comprising: program instructions to transmit, by a first node of a plurality of nodes, a change notification to a second node of the plurality of nodes, wherein the change notification indicates that the first node has changed from a first version to a second version; program instructions to receive, by the first node of the plurality of nodes, at least one change confirmation from the second node, the change confirmation confirming acknowledgment of the change notification by the second node and by a third node of the plurality of nodes; and program instructions to update, by the first node of the plurality of nodes, a version table of the first node to show that the second node and the third node know that the first node has changed from the first version to the second version, wherein the version table of the first node shows the first node's knowledge about what the second node knows about the version of the first node and a version of the third node, and about what the third node knows about the version of the first node and a version of the second node.

12 . The computer program product of claim 11 , wherein the program instructions to receive, by the first node of the plurality of nodes, at least one change confirmation from the second node include program instructions to receive a change confirmation from each node of the plurality of nodes.

13 . The computer program product of claim 11 , wherein the change confirmation confirming acknowledgment of the change notification by the second node and by the third node comprises a notification that the second node and the third node know that the first node has changed from the first version to the second version.

14 . The computer program product of claim 11 , wherein the program instructions further comprise:
program instructions to receive, by the first node of the plurality of nodes, a change notification from the second node, wherein the change notification indicates that the second node has changed from a first version to a second version; program instructions to transmit, by the first node of the plurality of nodes, a change confirmation to the second node, the change confirmation confirming acknowledgement of the received change notification; program instructions to update, by the first node of the plurality of nodes, an attribute table of the first node to show that the second node has changed from the first version to the second version; and program instructions to update, by the first node of the plurality of nodes, the version table of the first node to show that the second node knows that the second node has changed from the first version to the second version.

15 . The computer program product of claim 11 , wherein the program instructions further comprise:
program instructions to receive, by the first node of the plurality of nodes, a change notification of the third node from the second node, wherein the change notification indicates that the third node has changed from a first version to a second version; program instructions to transmit, by the first node of the plurality of nodes, a change confirmation to the second node for transmission to the third node, the change confirmation confirming acknowledgement of the received change notification; program instructions to update, by the first node of the plurality of nodes, an attribut

Assignees

• IBM

Inventors

• Anantharam Sushma
• Biswas Amitabha
• Ghosh Nirapada
• Padhye Harshad S

Classifications

• G06F16/27 Primary

  Replication, distribution or synchronisation of data between databases or within a distributed database system; Distributed database system architectures therefor · CPC title

• G06F17/30356

  Physics · mapped topic

• G06F17/30368 Primary

  Physics · mapped topic

• G06F16/2329

  using versioning · CPC title

• G06F16/2358 Primary

  Change logging, detection, and notification (replication G06F16/27) · CPC title