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Anonymous users2024-02-07Yes... There is a corresponding conversion procedure.
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Anonymous users2024-02-06Heterogeneous data is a collection of multiple pieces of data that are related.
A heterogeneous database system is a collection of related multiple database systems that can achieve data sharing and transparent access, and several database systems have existed since before joining the heterogeneous database system.
Each component of the external database has its own autonomy and data sharing, while realizing data sharing, each database system still has its own application characteristics, integrity control and security control.
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Anonymous users2024-02-05Heterogeneous data is a collection of multiple pieces of data that are related.
1. The heterogeneous database system is a collection of related multi-call database systems, which can realize data sharing and transparent access, and each database system already exists before joining the heterogeneous database system and has its own DBMS.
2. Each component of the heterogeneous database has its own autonomy, and while Boke realizes data sharing, each database system still retains its own application characteristics, integrity control and security control.
3. Each of its participating databases can be run on mainframe, minicomputer, workstation, PC or embedded system. The basic operating system of each database system can be UNIX, Windows NT, Linux, etc.
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Anonymous users2024-02-04Chemically, isomerism is a phenomenon in which compounds with the same chemical formula and the same chemical bonds have different atomic arrangements. It is divided into two categories: structural isomerism and stereoisomerism. The stereoisomerism is divided into three types: cis-trans isomerism (z) (e), optical isomerism, and conformational isomerism
Structural isomerism: Different structures cause isomerism, such as n-butane & isobutane, ethanol & methyl ether chemical properties are also completely different.
2. Stereoisomerism: the structure is similar, but the structure is different due to small deviations.
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Anonymous users2024-02-03According to the data characteristics of forestry information system, a heterogeneous data integration model based on WebSer-VICE was proposed without changing the storage and management mode of the original data, which used GML for spatial data integration and SVG for spatial data.
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Anonymous users2024-02-02A heterogeneous database system is a collection of related multiple database systems that can achieve data sharing and transparent access, and each database system already exists itself before joining the heterogeneous database system and has its own DBBS. Each component of a heterogeneous database has its own autonomy, enabling data sharing while maintaining its own application characteristics, integrity controls, and security controls. The heterogeneity of heterogeneous database systems is mainly reflected in the following aspects:
Heterogeneity of computer architecture.
Each participating database can run on a mainframe, minicomputer, workstation, PC, or embedded system.
Heterogeneity of the underlying operating system.
The basic operating system of each database system can be UNIX, Windows NT, Linux, etc.
Heterogeneity of the DMBS itself.
It can be an oracle or SQL server that is also a relational database system, or a database with different data models, such as relational, schematic, hierarchical, network, object-oriented, and functional databases, which together form a heterogeneous database system.
-The goal of the heterogeneous database system is to realize the merger and sharing of data and information resources, hardware equipment resources and human resources between different databases. One of the key points is to establish a global data schema or a global external view based on the local database schema. This global model is especially important for building advanced decision support systems.
- Large organizations have branches in many locations, and each sub-organization has its own information data in its database, while decision-makers are generally only concerned with the information that is described in the big picture and the global model. A description of the global pattern of heterogeneous databases, built on top of data warehouse technology, is a good solution. The data warehouse can collect information from multiple databases in the heterogeneous database system, and establish a unified global schema, while the collected data also supports access to historical data, and users can make decision-supported queries through the unified data interface provided by the data warehouse.
2. At present, there are three types of databases used in **, including soft access, mssql and mysql of sybase. They have their own advantages, and they are suitable for use in different conventions and languages. For example, most of the small and medium-sized asp** use access data stacks, and php** jujube grips mostly use mysql >>>More
The structure of the storage is the main basis for classifying the types of copy databases. In today's Internet, databases are usually divided into two categories, namely relational and non-relational databases. >>>More
The deletion operation in the data is irreparable, sometimes the data in the data table may be deleted due to misoperation, or the database crashes for other reasons, and all the data is lost, especially when there is a large amount of useful data in the database, then it is impossible for you to enter the data again from the beginning, this is the role of the backup database, back up the database, when the above situation occurs, you can restore the previous database through the backup file.
Key features: 1) Realize data sharing.
Data sharing includes all users who can access the data in the database at the same time, and also includes users who can use the database through interfaces in various ways and provide data sharing. >>>More
Database, a warehouse that holds data, a database system, a database, a database management system, hardware, and an operator. >>>More