DE102011018878B3 - Method for synchronizing data stored in database of distributed database system of e.g. smart phone, involves providing duplicator between databases for synchronizing databases, where databases are processed on fixed network node - Google Patents

Method for synchronizing data stored in database of distributed database system of e.g. smart phone, involves providing duplicator between databases for synchronizing databases, where databases are processed on fixed network node

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Publication number
DE102011018878B3
DE102011018878B3 DE102011018878A DE102011018878A DE102011018878B3 DE 102011018878 B3 DE102011018878 B3 DE 102011018878B3 DE 102011018878 A DE102011018878 A DE 102011018878A DE 102011018878 A DE102011018878 A DE 102011018878A DE 102011018878 B3 DE102011018878 B3 DE 102011018878B3
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databases
database
network nodes
14a
fixed network
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DE102011018878A
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German (de)
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Javier Mulero Chaves
Anton Donner
Stefan Erl
Chen Tang
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Deutsches Zentrum fur Luft- und Raumfahrt eV
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Deutsches Zentrum fur Luft- und Raumfahrt eV
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    • GPHYSICS
    • G06COMPUTING; CALCULATING; COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F16/00Information retrieval; Database structures therefor; File system structures therefor
    • G06F16/20Information retrieval; Database structures therefor; File system structures therefor of structured data, e.g. relational data
    • G06F16/27Replication, distribution or synchronisation of data between databases or within a distributed database system; Distributed database system architectures therefor

Abstract

The invention relates to a method for synchronizing the databases of databases in a distributed database system (10), wherein databases are located on mobile network nodes (12a to 12h) and on fixed network nodes (14a, 14b, 14c) that are at least partially over non-permanently available Network connections are interconnected. According to the invention, two databases (16a, 18a, 16b, 18b, 16c, 18c) are respectively operated on the fixed network nodes (14a to 14c). Between the first database (16a, 16b, 16c) and the second database (18a, 18b, 18c) there is provided a duplicator (20a, 20b, 20c) for synchronizing the first and second databases.

Description

  • The invention relates to a method for synchronizing the databases of databases in a distributed database system, wherein databases are located on mobile network nodes and on fixed network nodes, which are at least partially interconnected via non-permanently available network connections.
  • In this case, databases can be located on mobile and fixed network nodes. Mobile network nodes are often connected to the core network via non-permanently available network connections, that is, to the fixed network nodes. For example, individual instances of the distributed database system can be installed on mobile devices such as notebooks, tablet PCs, smartphones, etc., whereby the network connection of these devices can be wireless, so that relatively often connection impairments occur. Replication mechanisms of distributed database systems can not handle these link breaks or the associated change in the network topology by eliminating and reentry of instances not automated. The database instances installed on the network nodes thus lose their consistency. A change in the network topology requires either a manual reconfiguration of the replication system or corresponding complex signaling between the database instances. This can cause significant consumption of available bandwidth if there are frequent changes to the topology, such as may be caused when many mobile instances are connected to the network in poor reception. In particular, narrowband wireless connections to the mobile entities suffer from this additional signaling traffic that limits the available bandwidth for the actual transmission of payload data.
  • An example of a distributed database system is in 1 shown. Here are several fixed network nodes 14a . 14b . 14c a hull net 10a within which they are interconnected via stable network connections. In the edge area of the hull network 10a are the fixed network nodes 14a . 14b with the mobile network nodes 12a to 12f connected. These are unstable connections, such as wireless connections.
  • Many replication solutions operate on the master-slave or master-master principle, with only two instances connected at a time. The Ingres Replicator works on a peer-to-peer basis, meaning that an instance between two other instances can be configured to hand-off transactions from a source to a destination. Ingres Replicator uses a combination of source ID and transaction ID to identify transactions. To allow transactions to be forwarded from each source instance to each target instance, each database instance must be aware of appropriate forwarding rules for all database system sources and destinations. This corresponds to a global view of the distributed database system, which is subject to constant change as soon as mobile instances are present in the database system. These changes would have to be taken into account accordingly in the forwarding rules of all participating database instances.
  • DE 10 2009 038 672 A1 describes a method for performing program code updates in an at least partially meshed network having multiple node groups of network nodes of different types.
  • US 2006/0 155 827 A1 describes how to reconfigure a group of network nodes in an ad hoc network to improve the consistency of a software update.
  • US Pat. No. 5,995,981 concerns the initialization of data objects on distributed databases. Here, all nodes monitor the state of each other's nodes by receiving node status messages over the network.
  • US 5 907 849 A describes a method for recovering errors in distributed database systems.
  • The object of the invention is to provide a simplified method for synchronizing the databases of databases in a distributed database system with fixed and mobile network nodes.
  • The object is achieved according to the invention by the features of claim 1.
  • In the method according to the invention, databases of databases in a distributed database system are synchronized, wherein databases are located on mobile network nodes and fixed network nodes. These are at least partially interconnected via non-permanently available network connections. This means that at least some of the network nodes are connected to the database system via such network connections, which are not always available. These may be, for example, wireless connections.
  • According to the invention, two databases each are located on the fixed network nodes operated, wherein the first database exchanges data in particular exclusively with mobile network nodes and the second database exchanges data in particular exclusively with fixed network nodes. These fixed network nodes with which data is exchanged can have the same structure as the second database. Furthermore, a duplicator for synchronizing the first and second databases is arranged between the first and second databases.
  • The distributed database system is thus according to the invention divided into a stable trunk network and a variable number of mobile network nodes. Within the stable trunk network, fixed network nodes are interconnected via stable network connections. In the periphery of the trunk network, fixed network nodes are wirelessly connected to a variable number of mobile network nodes, for example.
  • The inventive method thus a simple synchronization of databases in a distributed database system is possible, with resources are spared because little signaling and configuration or configuration must be operated. The available bandwidth, for example in the case of wireless connections, can thus be used to transmit user data.
  • It is preferred that only existing database interfaces for connecting external programs are used for the connection and synchronization of the individual databases. As a result, a deep intervention in the internal processes of the database management system can be avoided.
  • As a result of the inventive decoupling of the first and second databases in a network node, a mobile network node can exchange data with every other fixed network node and is not bound to a specific fixed network node. It is therefore irrelevant which fixed reference node has a mobile network node. A change of the reference node thus has no effort for the signaling result.
  • Furthermore, the inventive decoupling of the first and second database in the fixed network node allows flexibility in terms of the number of mobile network nodes. According to the prior art, it is necessary for the database management system to have a global view of all the fixed and mobile network nodes, so that no flexibility in the number of mobile nodes is possible. According to the invention, it is not necessary to know the number of mobile network nodes, so that full scalability is given.
  • Furthermore, the features of the invention allow easier replaceability of individual replicator systems or synchronization solutions. In the respective first and second database in a fixed network node each adapted different solutions can be used, which meet the corresponding requirements best. These can also be solutions from different manufacturers.
  • It is preferred that the synchronization between the first and second databases in a fixed network node occur through the following steps:
    First, the duplicator is informed by one of the two databases about a data change made on this database. This step is called "notify".
  • Subsequently, the changed data is retrieved from this database by the duplicator. This step is also called a "fetch".
  • Subsequently, the fetched data is transmitted through the duplicator to the other database in the fixed network node. This step is called "Check and Insert".
  • Then the data can be further distributed from here using the regular replication mechanisms in the fixed node area.
  • The duplicator operates bidirectionally, that is, data is passed from the second database, that is, the database in the replication network in an inverted manner to the connected mobile instances. The above-mentioned process steps are formulated to be applicable for transferring the data through the duplicator in both directions.
  • The first and second database operating on the fixed network node may also be referred to as a table, where both tables or databases may reside on the same volume in the fixed network node.
  • It is preferred that data be synchronized between the fixed network nodes and / or between the fixed and mobile network nodes using conventional synchronization techniques. This means that the data exchange between the mobile database instances or network nodes and the respective first database in the fixed network nodes of the peripheral area of the trunk network takes place via customary synchronization methods. The same applies to the data exchange between the fixed nodes within the core network. Thus, no complex synchronization algorithms need to be implemented.
  • Forwarding rules for all other fixed network nodes within the database system are preferably stored in each fixed network node. However, these forwarding rules need not be stored in the mobile network nodes so that the required global view in the replication network is limited to the core system and not to the mobile network nodes. This is particularly easy to implement.
  • According to the invention, the fixed network nodes form a core or trunk network. It is preferred that the fixed network nodes from the edge area of the core network, which are connected to mobile network nodes, only need to know the mobile network nodes connected to them, but not other mobile network nodes of the database system.
  • Furthermore, it is preferred that no changes to the database management system are necessary when adding or removing mobile network nodes to or from the database system.
  • In the following, preferred embodiments of the invention will be explained with reference to figures.
  • Show it:
  • 1 a distributed database system according to the prior art,
  • 2 the exchange of data between the first and second database in a fixed network node, and
  • 3 an embodiment of a distributed database system according to the inventive method.
  • 1 has already been explained in connection with the prior art.
  • 2 shows the data exchange between the first database 16a and the second database 18a , both in the fixed node 14a are located. Between these two databases is the duplicator 20a arranged. The first database 16a Serves one or more mobile database instances running in 2 are not shown. The second database 18a Serves the fixed network nodes connected to it in 2 also not shown. The process is shown as an example only in one direction because of the better clarity.
  • According to 2 receives the first database 16a in a first step, data from a mobile database instance. In the second step ("notify") she informs about the duplicator 20a , This one brings in the first database 16a received data from this database 16a from (step 3: "fetch"). In steps 4 and 5 ("check and insert") the collected data is passed through the duplicator 20a to the second database 18a transfer. According to step 6, this data is transmitted to the fixed database instances that are connected to the second database 18a are connected.
  • In 3 is an embodiment of a distributed database system 10 represented, on which the inventive method can proceed.
  • Inside the hull network 10a are the solid nodes 14a . 14b . 14c arranged. Each of these fixed network nodes contains a first and a second database 16a . 18a ; 16b . 18b ; 16c . 18c , Continue to be in each fixed node 14a to 14c one duplicator each 20a to 20c ,
  • The fixed network nodes 14a . 14b in the edge area of the hull network 10a are with the mobile database instances 12a to 12h connected. The data from these mobile database instances to the fixed nodes 14a . 14b are transmitted in these fixed nodes via the duplicators 20a . 20b to the second database 18a . 18b transfer. From here, this data is transmitted to the other connected fixed network nodes.
  • The inventive method can be used in particular in the context of data management for civil protection. In addition to such an application, further applications are conceivable in which an instance of a distributed database system is to run on a mobile terminal. An implementation is possible in all areas of mobile data acquisition of logistics, goods and economy.

Claims (6)

  1. Method for synchronizing the databases of databases in a distributed database system ( 10 ), whereby databases on mobile network nodes ( 12a to 12h ) and on fixed network nodes ( 14a . 14b . 14c ), which are at least partially interconnected via non-permanently available network connections, characterized in that on the fixed network node ( 14a to 14c ) two databases each ( 16a . 18a ; 16b . 18b ; 16c . 18c ), the first database ( 16a . 16b . 16c ) Data, in particular exclusively with mobile network nodes ( 12a to 12h ) and the second database ( 18a . 18b . 18c ) Data, in particular exclusively with fixed network nodes ( 14a . 14b . 14c ) and between the first database ( 16a . 16b . 16c ) and the second database ( 18a . 18b . 18c ) a duplicator ( 20a . 20b . 20c ) is provided for synchronizing the first and second databases.
  2. Method according to claim 1, characterized in that the synchronization between the first database ( 16a to 16c ) and the second database ( 18a to 18c ) in a fixed network node ( 14a . 14b . 14c ) by the following steps: • informing the duplicator ( 20a . 20b . 20c ) by one of the two databases ( 16a . 18a ; 16b . 18b ; 16c . 18c ) about a data change made on it, • picking up the changed data from this database by the duplicator ( 20a . 20b . 20c ), • transfer of the retrieved data through the duplicator ( 20a . 20b . 20c ) to the other database in the fixed network node ( 14a . 14b . 14c ).
  3. Method according to claim 1 or 2, characterized in that the data between the fixed network nodes ( 14a to 14c ) and / or between the fixed and mobile network nodes ( 12a to 12h ) are synchronized using conventional synchronization techniques.
  4. Method according to one of claims 1 to 3, characterized in that in each fixed network node ( 14a to 14c ) Forwarding rules for all other fixed network nodes ( 14a to 14c ) in the database system ( 10 ), these forwarding rules being stored in the mobile network nodes ( 12a to 12h ) are not stored in particular.
  5. Method according to one of Claims 1 to 4, characterized in that the fixed network nodes ( 14a to 14c ) a core network ( 10a ) and the fixed network nodes ( 14a . 14b ) from the edge region of the core network ( 10a ) with mobile network nodes ( 12a to 12h ), only the mobile network nodes connected to them, but not other mobile network nodes of the database system ( 10 ).
  6. Method according to one of claims 1 to 5, characterized in that when adding or removing mobile network nodes ( 12a to 12h ) to or from the database system ( 10 ) no change of the database management system takes place.
DE102011018878A 2011-04-28 2011-04-28 Method for synchronizing data stored in database of distributed database system of e.g. smart phone, involves providing duplicator between databases for synchronizing databases, where databases are processed on fixed network node Active DE102011018878B3 (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019081086A1 (en) 2017-10-23 2019-05-02 Siemens Aktiengesellschaft Method and control system for controlling and/or monitoring devices
WO2019081071A1 (en) 2017-10-23 2019-05-02 Siemens Aktiengesellschaft Method and control system for controlling and/or monitoring devices
WO2019081434A1 (en) * 2017-10-23 2019-05-02 Siemens Aktiengesellschaft Method and control system for controlling and/or monitoring devices
WO2019141391A1 (en) * 2018-01-22 2019-07-25 Siemens Aktiengesellschaft Method and control system for controlling and/or monitoring devices
WO2019141392A1 (en) * 2018-01-22 2019-07-25 Siemens Aktiengesellschaft Method and system for controlling and/or monitoring devices
WO2019201461A1 (en) * 2018-04-18 2019-10-24 Siemens Aktiengesellschaft Method and control system for controlling and/or monitoring devices

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5907849A (en) * 1997-05-29 1999-05-25 International Business Machines Corporation Method and system for recovery in a partitioned shared nothing database system using virtual share disks
US5995981A (en) * 1997-06-16 1999-11-30 Telefonaktiebolaget Lm Ericsson Initialization of replicated data objects
US20060155827A1 (en) * 2002-08-22 2006-07-13 Docomo Laboratories Reconfiguration of a group of network nodes in an ad-hoc network
DE102009038672A1 (en) * 2009-08-24 2011-03-10 Siemens Aktiengesellschaft Method and apparatus for performing program code updates in a network

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5907849A (en) * 1997-05-29 1999-05-25 International Business Machines Corporation Method and system for recovery in a partitioned shared nothing database system using virtual share disks
US5995981A (en) * 1997-06-16 1999-11-30 Telefonaktiebolaget Lm Ericsson Initialization of replicated data objects
US20060155827A1 (en) * 2002-08-22 2006-07-13 Docomo Laboratories Reconfiguration of a group of network nodes in an ad-hoc network
DE102009038672A1 (en) * 2009-08-24 2011-03-10 Siemens Aktiengesellschaft Method and apparatus for performing program code updates in a network

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019081086A1 (en) 2017-10-23 2019-05-02 Siemens Aktiengesellschaft Method and control system for controlling and/or monitoring devices
WO2019081085A1 (en) 2017-10-23 2019-05-02 Siemens Aktiengesellschaft Method and control system for controlling and/or monitoring devices
WO2019081071A1 (en) 2017-10-23 2019-05-02 Siemens Aktiengesellschaft Method and control system for controlling and/or monitoring devices
WO2019081434A1 (en) * 2017-10-23 2019-05-02 Siemens Aktiengesellschaft Method and control system for controlling and/or monitoring devices
WO2019141391A1 (en) * 2018-01-22 2019-07-25 Siemens Aktiengesellschaft Method and control system for controlling and/or monitoring devices
WO2019141392A1 (en) * 2018-01-22 2019-07-25 Siemens Aktiengesellschaft Method and system for controlling and/or monitoring devices
WO2019201461A1 (en) * 2018-04-18 2019-10-24 Siemens Aktiengesellschaft Method and control system for controlling and/or monitoring devices

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