DBA Dictionary: Database design common vocabulary in English

1. Access method: This step includes storing and retrieving records from a file.

2. Alias (alias): Another name for a property. In SQL, you can replace the table name with an alias.

3. Alternate keys (alternate key, er/relationship model): Candidate keys for the primary health are not selected in the Entity/table.

4. Anomalies (exception) See Update anomalies

5. Application design: A phase of the database application life cycle, including the design of the user interface and the applications that use and process the database.

6. Attribute (attribute) (relational model): A property is a named column in a relationship.

7. Attribute (attribute) (ER model): a property of an entity or relationship.

8. Attribute Inheritance (attribute inheritance): A subclass member can have its own properties and inherit the process of those properties related to the superclass.

9. Base table: A named table whose records are physically stored in the database.

Binary relationship (two-yuan relationship): An ER term used to describe a relationship between two entities. For example, Panch has a staff.

bottom-up approach (bottom-up method): For database design, a design methodology, he starts by identifying each design build, and then aggregates the components into a single large unit. In database design, you can start the underlying design from a presentation property, and then combine these properties together to form a table that represents entities and relationships.

Business rules: Additional rules specified by the user or the manager of the database.

Candidate key (candidate key, er relationship model): Contains only the super-key that uniquely identifies the minimum number of attributes/columns that the entity must have.

Cardinality (Base): Describes the number of possible relationships for each participating entity.

Centralized approach (centralized method for database design): Merges the requirements of each user attempt into a collection of requirements for a new database application

Chasm Trap (PIT trap): Suppose there is a root between entities, but there is no pathway between some entities.

(client): a software application that requests services from one or more servers.

Clustering field (Cluster field): Records the total number of non-key fields used for the cluster (collection) navigation record, which have the same value on this field.

Clustering index (clustered index): The index defined on the cluster field of the file. A file has at most one primary index or one clustered index.

Column: Join attribute (attribute).

Complex relationship (complex relationship): a relationship with a degree greater than 2.

Composite attribute (composite property): A property consisting of multiple simple components.

Composite key (composite key): A primary health that contains multiple columns.

Concurrency control (concurrency control): A DBMS service that performs multiple XV and ensures data integrity simultaneously in a multiuser environment.

Constraint (Constraint): The database does not allow consistency rules that contain incorrect data.

Data conversion and loading: a phase of the database application life cycle, including converting existing data into a new database, and Nou Application conversion to a new database running under the sauce.

Data dictionary: Refer to the system catalog.

Data independence (data Independence): Part of the description of the application that uses the data. This means that if a new data structure is added to the database, or if the existing structure in the database is modified, the use of this database will be affected unless the application is not directly dependent on the part being modified.

Data Model: an integrated collection of concepts that describe data, relationships between data, and constraints on data.

Data redundancy (redundancy): see Redundant data (redundant).

Data security: Includes access to and use of database objects, such as tables and views, and actions that users can implement on those objects.

Database: A shared collection of logically related data (as well as descriptions of these data) used to resolve public

Information needs of the company.

Database design: A phase in the database application life cycle, including the design of a database that supports the operations and goals of the company.

Integrity Database integrity: Refers to the positive determination and consistency of stored data. Integrity is usually expressed in terms of constraints.

Database Management System,dbms: A software system that enables users to define, create, and maintain databases and control access to the database.

Database planning: It is possible to implement the management activities of the various stages of database application.

Panax Notoginseng database server: Same server.

DBMS engine (DBMS): Same server.

The DBMS selection (DBMS selection): A phase in the database application life cycle, including selecting an appropriate DBMS to support database applications.

Degree of a relationship (degree of relationship): the number of entities participating in a relationship.

Denormalization (Anti-normalization): Formally, this term refers to the modification of the basic table structure so that the new table is less normalized than the original table. But it can also be used to describe more broadly the case of two tables and a new table, and the new table has the same paradigm as the original table, but contains more null values than the original table.

Derived attribute (derived property): Represents a property whose value can be derived from the value of a related property and property set, which is not required in the entity.

Design methodology: A structured approach that uses processes, tools, and documentation to support and streamline the design process.

Disjoint constraint (no connection constraint): Describes the relationship between members of a subclass and indicates whether a superclass member has the potential to become a member of one or more subclasses.

Domain: The range of values for one or more properties.

Entity: A collection of objects of the same nature that is identified by the user or company and can exist independently.

Entity integrity (solid integrity): In a basic table, the value of the primary health column cannot be empty.

Entity occurrence (Entities): A uniquely identifiable object in an entity.

Entity-relationship model (Entity Relationship models): A detailed logical representation of a company's entities, attributes, and relationships.

Fact-Finding (Fact Finding): Use techniques such as interviewing and questioning to gather a formal process of the facts, needs and performance of the system.

The fan trap (sector traps): But a fan trap occurs when the two entities that fan out from the third entity have a 1:* relationship, but the two entities should have a direct relationship between them to provide the necessary information.

Field (field): Same tuple (tuple).

. File: A named collection of related records stored in the secondary master memory.

file-based System (file-based systems): A collection of files used to manage (create, insert, delete, update, and retrieve) data from one or more files and to produce an application (usually a report) based on the data in those files.

File organization: How the records in a file are arranged when the file is stored on disk.

(1NF, first normal form): The intersection of each column in the table and the record that contains the tangent to a table containing a value.

Foreign key: A column in a table or a collection of multiple columns that match the candidate keys in some other (or possibly the same) table.

4GL, Fourth-generation Language (Fourth generation language): a non-procedural language, such as SQL, which requires only the user to define what must be done, and 4GL is responsible for translating the operations into how they are implemented.

Full functional dependency (fully functional dependency): A column is functionally dependent on the composite master, but does not depend on any subset of the primary health condition.

Functional dependency (function dependent): Describes the relationship between the columns in the table.

Generalization (generalization): The process of minimizing differences between entities by identifying common characteristics between entities.

Generalization hierarchy (Generalization level

Structure): The same type level (type hierarchy).

Global Data Model: A data model representing the entire company (and part of a modeled company).

Implementation (Implementation): A phase in the database application life cycle, including the physical implementation of database and application design.

Index: A data structure that allows a DBMS to quickly place a particular record in a file, thereby speeding up the response to a user's query.

Infomation System (Information System): Resources that can collect, manage, control, and distribute data/information across the company.

Inheritance (inheritance): See Attribute Inheritance (Attribute inheritance).

Integrity constaints (integrity constraint): A constraint that prevents inconsistent data in the database.

Is-a hierarchy (Is-a hierarchy): The same type hierarchy (type hierarchy).

The local logical data model, the local logical data model, represents a combination of specific user views or user views.

Logical Database design: The process of building a model of a company's data based on a specific data model, but not on a specific DBMS and other physical conditions.

Meta-data (meta data): Data about data, see System catalog.

Mision Objective (Mission objective): identifies the specific tasks that the database must support.

Mission Statement (Mission Statement): Defines the primary goal of the database application.

Multiplicity (diversity): Defines the number of occurrences of an entity related to one occurrence of a related entity.

Multi-valued attribute (multi-valued attribute): A property that holds multiple values for the appearance of an entity.

Nonkey Attribute/column (non-key attribute/column): A property/column that is not part of a key.

The normal forms: a phase of the normalization process. The first three paradigms are firstly normal (1NF), second Normal (2NF), and third Normal (3NF).

Normalization (Normalization): a technology that produces features that are required, which can support the needs of users and companies.

Null (null value): Represents the value of a column that is not currently known or is not available for this record.

Operational maintenance (Operation Maintenance): a phase of the database application life cycle, including monitoring and maintenance of the system after installation of the operation.

Participation constraint (participation constraint, EER model): Determines whether each occurrence in a superclass must participate as a member of a subclass.

Participation constraint (Participation constraint, er model): Determines whether all or only certain entities appear to participate in the relationship.

Physical Database design: The process of generating a description of the implementation of the databases on level two storage, which describes the basic tables, the organization of the files, the indexes used to obtain effective access, and any instructions related to integrity constraints and security restrictions.

Primary Index (primary index): The index that is built on the ordered key field of the file. A file can have up to one primary index or one clustered index.

Primary key (master, er model): A candidate key used to identify the occurrence of each entity.

Primary Key (primary health, relational model): A candidate key used in a table to identify the uniqueness of a record.

Privileges (permissions): Allows the user to perform actions on a given base table and view.

Prototyping (prototype): a phase of the application life cycle of a database, including the working model of a Goujian database application.

Query-by-example (QBE): A non-procedural database language for relational DBMS. QBE is a graphical "point-by-Press" approach to querying a database.

RDBMS: Relational DBMS.

Record: The same tuple (tuple).

Recovery Control: Pepsi, the process of restoring a database to the correct state.

94. Rcursive relationship (Recursive relationship): a relationship in which a recursive relationship occurs when the same entity participates multiple times in different roles. For example staff supervises staff.

Redundant data (redundant): Duplicate data stored in multiple tables.

Referential integrity (referential integrity): If there are external keys in a table, the external health value must match the value of the candidate key for some records in the primary table.

Relation (Relationship): A relationship is a table, it also has columns and rows.

98. Relational model (relational model): A data model that represents data in the form of a table (or relationship).

relational database (relational database): A collection of normalized tables.

Relation (Relationship): meaningful relationships between entities.

101. Relationship occurrence (relationship occurrence): the only identifiable connection between two entities appears.

102. Requirements Collection and analysis (requirements collected in analytics): a phase in the life cycle of a database application that collects and analyzes information about the company that the database application supports, and uses that information to identify new database application requirements.

103. Row: The same tuple (tuple).

104. Second normal form (second paradigm): A table that is already in the first paradigm, while satisfying all non-primary columns can only be obtained from all columns that comprise the primary health.

Secondary index (Level two index): The index defined on the non-ordered field of the data file.

106. Security: Refers to preventing the database from being accessed by non-authorized users, including intentional and unintentional. RDBMS typically provides two types of security: Data security and system security.

107. Server: A software application that provides services to the customer who made the request. See two-tier/three-tier client-server architecture.

108. Simple attribute (easy property): Only one component's properties.

109. single-valued attribute (single value attribute): A property that has only one value for an entity.

Specialization (Special): The process of identifying the maximum number of inter-entity members by distinguishing the characteristics of the members between entities.

111. Specialization hierarchy (special hierarchy): The same type hierarchy (type hierarchy).

Structured SQL (Language, Structured Query Language): a non-procedural database language for RDBMS. In other words, you just need to specify what information you need without specifying how you want to get that information. SQL has been standardized by the International Organization for Standardization (ISO), so SQL is the formal and de facto standard language for defining and manipulating RDBMS.

113. Strong entity (strong entity): an entity that exists without relying on the existence of the primary health of other entities.

Subclass (Subclass): Entities in (superclass) entities that appear and maintain specific attributes and relationships and have different roles

Superclass (Superclass): An entity that holds public properties and relationships for all occurrences in an entity. See also specialization and generalization.

Superkey (Super-key, er model): an attribute or set of attributes that identifies each entity that appears.

117. Superkey (Hyper-key, relational model): A column or set of columns that uniquely identifies a record in a table.

118. System catalog: Holds information about database structures, users, applications, and so on.

119. System definition: A phase of the database application declaration cycle, which includes defining the database application and the scope and boundaries of his primary user view.

System security: Access and use at the system level to protect the database is inferior to the user name and password.

121. Table (table): Same relationship (relation).

122. Ternary relationship (ternary relationship): the relationship between three entities. such as the registers relationship between Panch,staff and member.

123. Testing (TEST): a phase of the database application life cycle, including executing applications and intentionally discovering errors.

124. Third normal form,3nf (third normal): A table that is already 1NF and 2NF, while the values of all non-primary health columns can only be obtained from the main column, not from the other columns.

3GL, Third-generation Language (third-generation language): a procedural language, such as COBOL, C, and C + +, which requires the user (usually a programmer) to specify what must be done and how to do it.

126. Three-tier Client-server Architecture (three-tier client-server architecture): consists of clients that process the user interface and the application server that processes the business logic, and data processing, and the database server is used to run the DBMS.

127. Top-down approach (top-down method for database design): A design approach that begins by defining the main structure of the system, and then progressively dividing the structures into smaller units. In a database design, begin this top-level step by identifying the relationship between the entity and the data, and then step through the details, such as the information you want to save about entities and relationships (as attributes) and all constraints on entities, relationships, and attributes.

Transaction: An action or series of actions performed by a user and an application that accesses or modifies the contents of a database.

129. Transaction processing MONITOR,TPM (transaction processing Monitor): A program that controls the conversion of data between client and server keys to provide a consistent environment for online transaction processing (OLTP).

Transitive dependency (transitive dependency): Assuming that A, B, and C are columns in a table, if B is dependent on a (a-->b), and C is dependent on B (b-->c), C is passed by B and relies on a (assuming a does not depend on B or C). This table is not 3NF if there is a transitive dependency on the main health. The transfer dependency must be removed from the table to meet the requirements of 3NF.

131. Tuple (tuple): A row of records in a relationship.

Two-tier client-server Architecture (two-tier client-server architecture) consists of a client application that handles the primary business and data processing logic, as well as a server program that manages and controls database access to the user's interface.

133. Type hierarchy (type hierarchy): One is to mention its subclasses and their superclass, and so on.

134. UML (Unified Modeling Language, Unified Modeling Language): A newer approach to object-oriented analysis and design methodologies introduced in the the 1980s and 90.

135. Update anomalies (updated exception): When the user view updates an identity that contains redundant data, it may cause inconsistencies. There are three types of exceptions: Insert, delete, and update.

136. User view: The requirements of a database application defined from the perspective of a particular job (such as a manager or administrator) or the business application area (such as market, employee, or Inventory Control).

137. View: A "virtual base table", which does not actually exist in the database, but is produced by the DBMS from the base tables it involves in the existing base.

138. View integration approach (view synthesis for database design): A requirement for each user view to build an independent data model that represents the user's attempt at the bottom. In the database design phase, the resulting database model is merged into a larger model.

DBA Dictionary: Database design common vocabulary in English