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What is the difference between data model and schema in database?
Wiki User
∙ 10y ago
As I understand it, a database schema is a physical entity, it describes the structure of exactly how the data is stored and is itself stored by DBMS for reference. Data model, on the other hand, is an abstract representation of database.
Wiki User
∙ 10y ago
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What is the difference between schema and database?
Database schema are the logical structure of entities (tables or object classes) and their relationships (keys, or object associations) in a database. Schema can exist at different levels of abstraction (see: en.wikipedia.org/wiki/Database_schema). Schema themselves may or may not exist as such in a database. In general schema at the higher levels of abstraction are design models that are captured in printed documents, and authored by business analysts and database designers, rather than created by database programmers and stored in the database itself. But in some types of databases, schema at any level of abstaction can be realized physically. In Oracle databases, schema can be realized as schema objects, which are a part of an Oracle database. These schema objects may represent a human user's conceptual model of the knowledge captured in an enterprise database. Thus defined, there can be many schema that can be associated with one physical database. In other kinds of relational database, an abstract user's schema can be represented by logically linked metadata, views, and stored procedures assocated with a user class. In object-oriented databases, especially those based on the highly self-referential language Smalltalk (e.g. Gemstone/S), schema are realized as "physical" objects in the database as a matter of course, as well as in the logical models captured in design documents. The schema objects in such databases are, in essence, the classes comprising the infrastructure of the database or application. Oracle-style user schema are readily created; these would be realized as user interface orchestrator classes.
What is the difference between a verbal model and a algebraic model?
The differnce between a verbal model and a algebraic model is that a verbal model is an equation written in words and a algebraic model is solving the equation from the verbal model.
What are the difference between Rational Unified Process and Spiral model?
It's uml base model usely use of use case design and spiral model Risk driven approchs
What is a relational database query and Explain with an example?
A relational database matches data by using common characteristics found within the data set. The resulting groups of data are organized and are much easier for many people to understand.For example, a data set containing all the real-estate transactions in a town can be grouped by the year each transaction occurred, the sale price, a buyer's last name and so on. Such a grouping uses the relational model (a technical term for this is schema). Hence, such a database is called a "relational database."The software used to do this grouping is called a relational database management system (RDBMS). The term "relational database" often refers to this type of software.Relational databases are currently the predominant choice in storing data like financial records, medical records, personal information and manufacturing and logistical data.
Advantage of relational model over hierarchical model?
Use of primary keys less data redundancy compatible with inconsistencies associated with database anomalies
What are the difference between hierarchical database and network database?
Hierarchical databases organize data in a tree-like structure with parent-child relationships and a strict one-to-many hierarchy, while network databases use a more flexible model with many-to-many relationships through pointers or links between records. Hierarchical databases are faster for accessing data along predefined paths, while network databases allow for more complex data relationships but can be more complex to manage.
What is the difference between schema and database?
Database schema are the logical structure of entities (tables or object classes) and their relationships (keys, or object associations) in a database. Schema can exist at different levels of abstraction (see: en.wikipedia.org/wiki/Database_schema). Schema themselves may or may not exist as such in a database. In general schema at the higher levels of abstraction are design models that are captured in printed documents, and authored by business analysts and database designers, rather than created by database programmers and stored in the database itself. But in some types of databases, schema at any level of abstaction can be realized physically. In Oracle databases, schema can be realized as schema objects, which are a part of an Oracle database. These schema objects may represent a human user's conceptual model of the knowledge captured in an enterprise database. Thus defined, there can be many schema that can be associated with one physical database. In other kinds of relational database, an abstract user's schema can be represented by logically linked metadata, views, and stored procedures assocated with a user class. In object-oriented databases, especially those based on the highly self-referential language Smalltalk (e.g. Gemstone/S), schema are realized as "physical" objects in the database as a matter of course, as well as in the logical models captured in design documents. The schema objects in such databases are, in essence, the classes comprising the infrastructure of the database or application. Oracle-style user schema are readily created; these would be realized as user interface orchestrator classes.
What is the difference between data model and database model?
A database is a collection of tables that is used for some purpose (typically an application of some sort). A database model is a description of that database, and describes how the tables relate to each other. Typically, a model is designed first, then the actual database is implemented using the model as a blueprint.
What does a databse do?
database is a structured collection of records or data that is stored in a computer system. A database usually contains software so that a person or program can use it to answer queries or extract desired information.[1] The term "database" refers to the collection of related records, and the software should be referred to as the database management system (DBMS). Other terms for DBMS are database manager or database system. When the context is ambiguous, however, many database administrators and programmers use the term "database" to refer to both the data collection and the software that enables it to be accessed. Typically, for a given database, there is a structural description of the type of facts held in that database: this description is known as a schema. The schema describes the objects that are represented in the database, and the relationships among them. There are a number of different ways of organizing a schema, that is, of modeling the database structure: these are known as database models (or data models). The model in most common use today is the relational model. Other models such as the hierarchical model and the network model use a more explicit representation of relationships (see below for explanation of the various database models). Database management systems are usually categorized according to the database model that they support. The data model tends to determine the query languages that are available to access the database. A great deal of the internal engineering of a DBMS, however, is independent of the data model, and is concerned with managing factors such as performance, concurrency, integrity, and recovery from hardware failures. In these areas there are large differences between products.
What is difference between object and entity?
A database object is represented as one of the following: database, schema, table, column, primary key, and foreign key A database Entity is: An entity is a thing or object of importance about which data must be captured. All things aren't entities - only those about which information should be captured. Information about an entity is captured in the form of attributes and/or relationships. If something is a candidate for being an entity and it has no attributes or relationships, it isn't an entity. Database entities appear in a data model as a box with a title. The title is the name of the entity.
What is the advantage of hibernate in j2ee?
Hibernate is capable of mapping all Object Oriented relationships (such as inheritance,interfaces, associations, composition, ternary associations) between objects. Hibernate follows both Bottom-up (existing database to OO model) and Top-down (OOModel to design the database schema) approaches: asanthine s
What are the advantages and disadvantages of network data model?
Network data model is just like a normal database model. In network model the data is seen as related to each other by links. Or we can say the relation between the data is represented by links.
Basic differences between conceptual schema and a physical schema?
* Conceptual - a model that captured the essential data that needed to be stored and the relationships between elements * * ** Physical - the on disk representation of data that accounts for layout, partitioning, index, space management, etc.
What is the difference between a repository and a database?
The Metasafe Repository is a (DMBS) Database Management System. There are many types of DMBS with different core models: Oracles, SQLServer, MySQL are based on the "relational model" which is constructed from tables. IMS the database from IBM is based on a hierachical model. Etc. Metasafe is based on an entity-relationship model, which means that is handles "entities" and "relationships between entities". This is the difference. What do they have in common? A (proper) database can be used by many users in parallel. It guarantees that a set of changes (a transaction) is processed completely or not all to make sure that the database is allways in a consistent state. A DMBS has also an access language (in case of Metasafe erSQL) and an API to access the data in the database. Last update on 04.11.2011 by Patrick Landolt.
Difference between multistore and working model memory?
what is the difference between the memory store model and the working memory model?
What is dbms architecture?
1. External view : this is a highest level of abstraction as seen by user. This level of abstraction describes only the part of entry database. It is based on the conceptual model, is the end user view of data environment. Each external view described by means of a schema called an external schema or subschema. The external schema consists of the definition of the logical records and the relationships in the external view. The external schema also contains he method of deriving the objects in the external view from the objects in the conceptual view. The object include entities, attributes and relationships.2. Conceptual level : at this level of database abstraction all the database entities and the relationships among them are included. One conceptual view represents the entire database. the conceptual schema defines ths conceptual view. It there is only one conceptual schema per database. This schema also contains the method deriving from the objects in the conceptual view from the objects in the internal view.. at this level a database is described logically rather then physically in term of data structure.3. Internal(physical) level : this lowest level of abstraction. it closest to physical storage device. It describes how data are actually stored on the storage medium. The internal schema, which contains the definition of the stored record, the method representing the data fields, expresses the internal view and the access aids used.
What difference between medical model and holistic model of care?
difference between holistic and medical models
