Data delta synchronization method and system

Abstract

This invention provides a data incremental synchronization method and system. The method is applied to a data incremental synchronization system, including a first database, a server, a set of terminals, and a second database. The method includes: the server obtaining logs from the first database, parsing the logs, and storing the parsing results; the set of terminals determining, through the server, whether the data in the first database has changed; if the set of terminals determines that the data in the first database has changed, each terminal in the set selects a preset number of terminals as execution terminals according to a preset load balancing and trust level strategy; the execution terminals obtain the changed data in the first database corresponding to the parsing results from the server and incrementally synchronize the changed data in the first database to the second database. This invention can improve the efficiency and security of data incremental synchronization.

Description

Technical Field

[0001] This invention belongs to the field of computer technology, and in particular relates to a method and system for incremental data synchronization. Background Technology

[0002] The rapid development of the internet has promoted the transformation and upgrading of traditional industries. In the process of integrating with the internet, more and more enterprises, institutions, and government systems have realized the informatization of their operations. However, these informatization systems are not unified, and it is difficult to share data between the databases of different systems.

[0003] However, in many application scenarios, data sharing and synchronization between different databases are required. Data synchronization refers to the process of synchronizing changes to other databases when data in one database changes, in order to ensure data consistency throughout the system.

[0004] Existing data synchronization methods are divided into two categories: full synchronization and incremental synchronization. Full synchronization involves reading all data from the source database, transforming it, and then applying it to the target database. While simple to implement, this method is time-consuming and suffers from poor real-time data consistency. Incremental synchronization, on the other hand, synchronizes only data that has changed since the last synchronization. This method is faster and offers better real-time data consistency.

[0005] Improving the efficiency and security of incremental data synchronization is an urgent problem to be solved in existing incremental synchronization solutions. Summary of the Invention

[0006] In view of this, the present invention provides a data incremental synchronization method and system that can improve the efficiency and security of data incremental synchronization.

[0007] A first aspect of this invention provides a data incremental synchronization method. This method is applied to a data incremental synchronization system, which includes a first database, a server, a terminal set, and a second database. The terminal set contains N terminals, where N is greater than or equal to 2. The server communicates with the first database and the terminal set, respectively. The terminal set also communicates with the second database. The method includes:

[0008] The server retrieves the logs from the first database, parses the logs, and stores the parsing results.

[0009] The terminal set determines whether the data in the first database has changed through the server, wherein the server determines whether the data in the first database has changed based on the parsing result;

[0010] If the terminal set determines that the data in the first database has changed, then each terminal in the terminal set selects a preset number of terminals as execution terminals according to a preset load balancing and trust strategy.

[0011] The execution terminal obtains the changed data in the first database corresponding to the parsing result from the server, and synchronizes the incremental changes in the first database to the second database.

[0012] Secondly, embodiments of the present invention provide a data incremental synchronization system, which includes a first database, a server, a terminal set, and a second database, wherein the terminal set contains N terminals, where N is greater than or equal to 2, the server communicates with the first database and the terminal set respectively, and the terminal set also communicates with the second database, and the data incremental synchronization system is used to implement the steps of the method described in the first aspect above.

[0013] This invention provides a data incremental synchronization method and system. By using a preset load balancing and trust strategy, a preset number of terminals are selected as execution terminals, which then complete the work of synchronizing incremental data to a second database, thereby improving the efficiency and security of data incremental synchronization. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the data incremental synchronization system provided in an embodiment of the present invention;

[0016] Figure 2 This is a flowchart illustrating the implementation of a data incremental synchronization method provided in an embodiment of the present invention.

[0017] Figure 3 This is a flowchart illustrating the implementation of another data incremental synchronization method provided in this embodiment of the invention.

[0018] Figure 4 This is a flowchart illustrating the implementation of another data incremental synchronization method provided in this embodiment of the invention.

[0019] Figure 5 This is a flowchart illustrating the implementation of another data incremental synchronization method provided in this embodiment of the invention.

[0020] Figure 6This is a flowchart illustrating the implementation of another data incremental synchronization method provided in this embodiment of the invention.

[0021] Figure 7 This is a schematic diagram of a terminal or server provided in an embodiment of the present invention. Detailed Implementation

[0022] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the invention with unnecessary detail.

[0023] To make the objectives, technical solutions, and advantages of the present invention clearer, specific embodiments will be described below in conjunction with the accompanying drawings.

[0024] See Figure 1 This diagram illustrates a data incremental synchronization system provided by an embodiment of the present invention. The data incremental synchronization method provided by the present invention is applied to a system such as... Figure 1 The data incremental synchronization system shown in the figure includes a first database, a server, a terminal set, and a second database. The terminal set contains N terminals, where N is greater than or equal to 2. The server communicates with both the first database and the terminal set. The terminal set also communicates with the second database. Figure 2 The method includes:

[0025] S101, the server retrieves the logs from the first database, parses the logs, and stores the parsing results.

[0026] Taking MySQL database as an example, MySQL logs include binary logs. The binary logs record all modification operations on the MySQL database, including data modifications such as insert, update, and delete, as well as modifications to data tables such as CREATE. It is a prerequisite for MySQL database replication, backup, and recovery. If the first database is a MySQL database, then the logs of the first database must contain at least the binary logs of the MySQL database.

[0027] Of course, in this embodiment of the invention, the types of the first database, the second database, and the log are not limited. Any type of database that can implement the data increment method provided by this invention is within the protection scope of this invention.

[0028] Specifically, the server establishes a connection with the first database and sends a log query message to it. This message includes the log filename and its offset within the log file. Upon receiving the message, the first database pushes all log events recorded after the specified offset position to the server. When data changes occur in the first database, it writes the change as a log event to its own log file and pushes this event to the server. The server receives and parses this log event to obtain the complete data change information.

[0029] S102, the terminal set determines whether the data in the first database has changed through the server, wherein the server determines whether the data in the first database has changed based on the parsing result.

[0030] The server parses the logs of the first database to determine if data changes have occurred in that database. The terminal set uses the server to determine if data changes have occurred in the first sub-database in ways including, but not limited to, the following two methods:

[0031] In one optional implementation, if the server determines that the data in the first database has changed based on the parsing result, the server broadcasts a message to the terminal set, the broadcast message indicating that the data in the first database has changed;

[0032] In another optional implementation, any terminal in the terminal set sends a query message to the server at preset time intervals. The query message is used to query whether the first database has undergone data changes within the time period corresponding to the preset time interval.

[0033] S103, if the terminal set determines that the data in the first database has changed, then each terminal in the terminal set selects a preset number of terminals as execution terminals according to the preset load balancing and trust policies.

[0034] In this step, trust level refers to the server's trust in the terminal, and load balancing refers to the performance index of the terminal's own central processing unit (CPU). This step selects a preset number of terminals with good overall trust level and load balancing capabilities as execution terminals.

[0035] S104, the execution terminal obtains the changed data in the first database corresponding to the parsing result from the server, and synchronizes the incremental changes in the first database to the second database.

[0036] Since the execution terminal in this step is a terminal with good overall trust and load balancing capabilities selected in step S103, the efficiency and security of incremental data synchronization during the execution of step S104 are improved.

[0037] As can be seen from the above, the present invention establishes a terminal cluster and selects a preset number of terminals with good combined trust and load balancing capabilities as execution terminals to synchronize incremental data from the first database to the second database, thereby improving the efficiency and security of incremental data synchronization.

[0038] Figure 3 This diagram illustrates an implementation flowchart of another data incremental synchronization method provided by an embodiment of the present invention. This embodiment is mainly used to implement... Figure 2 Step S103 in the corresponding embodiment, combined with Figure 3 The details are as follows:

[0039] S1031, For any terminal in the terminal set, the terminal obtains the server's trust score for the terminal.

[0040] Optionally, the server assigns a trust score to the terminal based on preset trust metrics. These preset trust metrics include, but are not limited to, the terminal's network location information, device type, network access method, historical packet loss rate, and historical average network latency. The server then sends the trust score to the terminal.

[0041] S1032, the terminal obtains its own data processing capability score based on the performance indicators of its own central processing unit (CPU).

[0042] Optionally, the CPU performance of the terminal may include, but is not limited to, the CPU cache capacity and utilization of the terminal.

[0043] S1033, the terminal obtains its own comprehensive score based on the trust score, its own data processing capability score, and the preset weight value.

[0044] Optionally, the terminal calculates its overall score using the following formula:

[0045] w z =ρ1w1+ρ2w2

[0046] Among them, w z The overall score for the terminal is calculated as follows: ρ1 and ρ2 are preset weight coefficients, and the sum of ρ1 and ρ2 is 1. w1 is the server's trust score for the terminal, and w2 is the terminal's own data processing capability score.

[0047] S1034, the terminal broadcasts its overall score to the set of terminals.

[0048] S1035, based on the comprehensive score of each terminal, a preset number of terminals are selected as execution terminals from all terminals in the terminal set.

[0049] Optionally, all terminals in the terminal set are sorted in descending order of their comprehensive scores, and the top preset number of terminals in the sorting results are selected as the execution terminals.

[0050] As can be seen from the above, the present invention selects a preset number of terminals with good combined trust and load balancing capabilities in the terminal cluster as execution terminals to synchronize incremental data from the first database to the second database, thereby improving the efficiency and security of incremental data synchronization.

[0051] Figure 4 This diagram illustrates the implementation flowchart of another data incremental synchronization method provided by an embodiment of the present invention, in conjunction with... Figure 4 The details are as follows:

[0052] S401, the server divides the parsed results into multiple categories, each with a corresponding category label.

[0053] For example, the data in the first database is divided into three categories: government information, financial data, and news. In some application scenarios, the second database may not require, or may not have the necessary permissions to incrementally synchronize all types of data from the first database; it may only require, or have the necessary permissions to incrementally synchronize one or a few types of data.

[0054] In this application scenario, the server divides the parsed results into multiple categories, with each category corresponding to a category label.

[0055] S402, the server determines the authorized category label corresponding to the execution terminal.

[0056] The execution terminal is used to incrementally synchronize data from the first database to the second database. For example, the second database only needs, or has only permission to perform incremental data synchronization for one or more categories of data. In this case, all terminals in the terminal set are pre-authorized to synchronize the category labels corresponding to one or more categories of data for the second database.

[0057] S403, the server obtains the changed data in the first database corresponding to the authorized category tag of the execution terminal, and sends the data to the execution terminal. Here, any two terminals in the terminal set have the same authorized category tag, and the preset number is 1.

[0058] In the application scenario of this invention embodiment, any two terminals in the terminal set have the same authorized category label, the preset number is 1, and only one terminal in the terminal set is selected as the execution terminal.

[0059] For example, if all terminals in the terminal set are authorized with the data category label "financial data", then the executing terminal will send the changed data in the first database corresponding to the category label "financial data" to the executing terminal.

[0060] This invention classifies the data in the first database, ensuring that the execution terminal can only obtain data from the first database within the authorized scope and incrementally synchronizes it to the second database. This not only reduces the amount of data transmitted but also further ensures data security.

[0061] Figure 5 This diagram illustrates the implementation flowchart of another data incremental synchronization method provided by an embodiment of the present invention, in conjunction with... Figure 5 The details are as follows:

[0062] S501, the server divides the parsed results into M categories, each category corresponds to a category label, and the content of any two categories does not overlap, where M is a positive integer greater than or equal to 2.

[0063] For example, the data in the first database is divided into the following three categories: government information, financial data, and news.

[0064] When the data incremental synchronization task is very large, it is very inefficient to perform incremental synchronization with only one execution terminal. In this application scenario, the server divides the parsing results into multiple categories, and each category corresponds to a category label.

[0065] S502, the preset number is M, and any two execution terminals among the M execution terminals have different authorized category tags. For any execution terminal among the M execution terminals, the server obtains the changed data in the first database corresponding to the authorized category tag according to the authorized category tag of the execution terminal, and sends the data to the execution terminal.

[0066] For example, the data in the first database is divided into three categories: government information, financial data, and news, where M=3.

[0067] Three execution terminals are selected from the terminal set. If the authorized category label of terminal 1 is "Government Information", then terminal 1 will synchronize the incremental data of "Government Information" to the second database. If the authorized category label of terminal 2 is "Financial Data", then terminal 2 will synchronize the incremental data of "Financial Data" to the second database. If the authorized category label of terminal 3 is "News and Messages", then terminal 3 will synchronize the incremental data of "News and Messages" to the second database.

[0068] In this invention, the server divides the parsing results into M categories, and M execution terminals respectively perform incremental synchronization work from the first database to the second database corresponding to one of the category labels, thereby improving the efficiency of incremental synchronization.

[0069] Figure 6 This diagram illustrates the implementation flowchart of another data incremental synchronization method provided by an embodiment of the present invention, in conjunction with... Figure 6 The details are as follows:

[0070] S601, the server divides the parsed results into multiple levels.

[0071] Based on the importance of the data in the first database, the parsing results are divided into multiple levels.

[0072] For example, the server divides the parsed results into three levels: Level 1 data, Level 2 data, and Level 3 data. The data levels are from lowest to highest as follows: Level 1 data, Level 2 data, and Level 3 data.

[0073] S602, the server determines the authorized level corresponding to the execution terminal.

[0074] The second database is only authorized to synchronize data at a certain level. For example, the second database is only allowed to synchronize data at level 2 and below. In this case, each terminal in the terminal set is authorized at level 2.

[0075] S603, the server obtains data from the first database that has changed and is at or below the authorization level according to the authorization level corresponding to the execution terminal, and sends the data to the execution terminal. Here, any two terminals in the terminal set have the same authorization level, and the preset number is 1.

[0076] In this embodiment of the invention, any two terminals in the terminal set are authorized at the same level, the preset number is 1, and only one terminal is selected from the terminal set as the execution terminal.

[0077] In this embodiment of the invention, by classifying the data in the first database by level, the terminals in the terminal set can only synchronize data from the first database that is at the same or lower level than their authorization level to the second database, thereby ensuring the security of incremental data synchronization.

[0078] Optionally, the first database and the second database are databases of the same data type, or the first database and the second database are databases of different data types. If the first database and the second database are databases of different data types, then synchronizing the incremental changes in the first database to the second database also includes: processing the changes in the first database to make the data format of the changes in the first database the same as the data format of the second database.

[0079] This invention can be applied to incremental data synchronization between mainstream databases, including but not limited to MySQL databases, SQL Server databases, etc.

[0080] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0081] Figure 7 This is a schematic diagram of a terminal or server provided in an embodiment of the present invention. For example... Figure 7 As shown, the terminal or server 7 in this embodiment includes: a processor 70, a memory 71, and a computer program 72 stored in the memory 71 and executable on the processor 70. When the processor 70 executes the computer program 72, it implements the steps in the various data incremental synchronization method embodiments described above, for example... Figure 2 Steps 101 to 104 are shown.

[0082] For example, the computer program 72 may be divided into one or more modules / units, which are stored in the memory 71 and executed by the processor 70 to complete the present invention. The one or more modules / units may be a series of computer program instruction segments capable of performing a specific function, which describe the execution process of the computer program 72 in the terminal 7.

[0083] The terminal 7 can be a computing device such as a desktop computer, laptop, handheld computer, or cloud server. The terminal 7 may include, but is not limited to, a processor 70 and a memory 71. Those skilled in the art will understand that... Figure 7 This is merely an example of terminal 7 and does not constitute a limitation on terminal 7. It may include more or fewer components than shown, or combine certain components, or different components. For example, the terminal may also include input / output devices, network access devices, buses, etc.

[0084] The processor 70 may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0085] The memory 71 can be an internal storage unit of the terminal 7, such as a hard disk or memory of the terminal 7. The memory 71 can also be an external storage device of the terminal 7, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on the terminal 7. Furthermore, the memory 71 can include both internal storage units and external storage devices of the terminal 7. The memory 71 is used to store the computer program and other programs and data required by the terminal. The memory 71 can also be used to temporarily store data that has been output or will be output.

[0086] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0087] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0088] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0089] In the embodiments provided by this invention, it should be understood that the disclosed devices / terminals and methods can be implemented in other ways. For example, the device / terminal embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0090] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0091] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0092] If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the above-described data incremental synchronization method embodiments. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0093] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A method of data incremental synchronization, the method comprising: This method is applied to a data incremental synchronization system, which includes a first database, a server, a terminal set, and a second database. The terminal set contains N terminals, where N is greater than or equal to 2. The server communicates with both the first database and the terminal set, and the terminal set also communicates with the second database. The method includes: The server retrieves the logs from the first database, parses the logs, and stores the parsing results. The terminal set determines whether the data in the first database has changed through the server, wherein the server determines whether the data in the first database has changed based on the parsing result; If the terminal set determines that the data in the first database has changed, then each terminal in the terminal set selects a preset number of terminals as execution terminals according to a preset load balancing and trust strategy. The execution terminal obtains the changed data in the first database corresponding to the parsing result from the server, and incrementally synchronizes the changed data in the first database to the second database; Each terminal in the terminal set selects a preset number of terminals as execution terminals according to a preset load balancing and trust strategy, including: for any terminal in the terminal set, the terminal obtains the server's trust score for the terminal; the terminal obtains its own data processing capability score based on its own central processing unit (CPU) performance indicators; the terminal obtains its own comprehensive score based on the trust score, its own data processing capability score, and a preset weight value; the terminal broadcasts its comprehensive score to the terminal set; and all terminals in the terminal set elect a preset number of terminals as execution terminals based on each terminal's comprehensive score. The process of obtaining the trust score from the server for the terminal includes: the server assigning a trust score to the terminal based on a preset trust index corresponding to the terminal, wherein the preset trust index corresponding to the terminal includes the terminal's network location information, the terminal's device type, the terminal's network access method, the terminal's historical packet loss rate, and the terminal's historical average network latency; and the server sending the trust score to the terminal. CPU performance includes the CPU's cache capacity and utilization rate.

2. The method according to claim 1, characterized in that, The terminal set determines whether the data in the first database has changed through the server, including: If the server determines that the data in the first database has changed based on the parsing result, the server broadcasts a message to the terminal set, the broadcast message indicating that the data in the first database has changed; Alternatively, any terminal in the terminal set may send a query message to the server at preset time intervals. The query message is used to query whether the first database has undergone data changes within the time period corresponding to the preset time interval.

3. The method according to claim 1, characterized in that, Based on the comprehensive score of each terminal, a predetermined number of terminals are selected as execution terminals from all terminals in the terminal set, including: All terminals in the terminal set are sorted in descending order of their comprehensive scores, and the top preset number of terminals in the sorting results are selected as the execution terminals.

4. The method according to claim 1, characterized in that, The method also includes: The server divides the parsing results into multiple categories, each category corresponding to a category label; The execution terminal obtains the changed data in the first database corresponding to the parsing result from the server, including: The server determines the authorized category label corresponding to the execution terminal; The server obtains the changed data in the first database corresponding to the authorized category tag of the execution terminal, and sends the data to the execution terminal. The authorized category tags of any two terminals in the terminal set are the same, and the preset number is 1.

5. The method according to claim 1, characterized in that, The method also includes: The server divides the parsing results into M categories, each category corresponding to a category label, and the content of any two categories does not overlap, where M is a positive integer greater than or equal to 2; The execution terminal obtains the changed data in the first database corresponding to the parsing result from the server, including: The preset number is M. Any two execution terminals among the M execution terminals have different authorized category tags. For any execution terminal among the M execution terminals, the server obtains the changed data in the first database corresponding to the authorized category tag according to the authorized category tag of the execution terminal, and sends the data to the execution terminal.

6. The method according to claim 1, characterized in that, The method also includes: The server divides the parsing results into multiple levels; The execution terminal obtains the changed data in the first database corresponding to the parsing result from the server, including: The server determines the authorized level corresponding to the execution terminal; The server obtains data in the first database that has changed and is at or below the authorization level corresponding to the execution terminal, and sends the data to the execution terminal. The authorization levels of any two terminals in the terminal set are the same, and the preset number is 1.

7. The method according to any one of claims 1 to 6, characterized in that, The first database and the second database are databases of the same data type, or the first database and the second database are databases of different data types; If the first database and the second database are databases of different data types, then the step of incrementally synchronizing the changed data in the first database to the second database also includes: The modified data in the first database is processed to make the data format of the modified data in the first database the same as the data format of the second database.

8. A data incremental synchronization system, characterized in that, The system includes a first database, a server, a terminal set, and a second database, wherein the terminal set contains N terminals, where N is greater than or equal to 2. The server communicates with the first database and the terminal set, respectively, and the terminal set also communicates with the second database. The data incremental synchronization system is used to implement the steps of the method described in any one of claims 1 to 7 above.

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