[Switch] database design vocabulary
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1. Access
Method: This step includes storing and retrieving records from files.
2. Alias (alias): Another name of an attribute. In SQL, you can replace the table name with an alias.
3.
Alternate keys (backup key, ER/relational model): The candidate key is not selected as the master key in the entity/table.
4. For anomalies (exception), see update exception (Update
Anomalies)
5. Application
DESIGN: a stage in the lifecycle of a database application, including designing a user interface and using and processing database applications.
6.
Attribute (relational model): an attribute is a column named in a link.
7. Attribute (attribute) (ER Model): a property in an object or link.
8.
Attribute inheritance: a subclass member can have its own attributes and inherit the attributes related to the superclass.
9. Base
Table (basic table): A named table with physical records stored in the database.
10. Binary
Relationship: an ER term used to describe the relationship between two entities. For example, panch has staff.
11. Bottom-up
Approach (bottom-up method): used for database design, a design methodology that starts from identifying each design build and then aggregates these components into a large unit. In database design, you can start the underlying design from the representation attribute, and then combine these attributes to form a table that represents the object and link.
12.
Business Rules: an additional rule specified by a user or database administrator.
13. Candidate
Key (Candidate Key, er relational model): contains only the superkeys of the minimum number of attributes/columns required to uniquely identify an object.
14.
Cardinality (base): Describes the number of possible relationships involved in each object.
15. Centralized
Approach (centralized method for database design): a set of requirements that every user tries to combine into a new database application
16. chasm
Trap: Assume that there is one object, but some entities do not have a path.
17.
Client: a software application that requests services from one or more servers.
18. Clustering
Field (cluster field): records the total number of non-key fields used for the cluster (SET) flight records. These rows have the same value on this field.
19. Clustering
Index: The index defined on the cluster field of the file. A file can have at most one primary index or one cluster index.
20.
Column: attribute ).
21. complex relationship (complex relationship): relationship with a degree greater than 2.
22.
Composite attribute: an attribute composed of multiple simple components.
23. Composite
Key: The primary key that contains multiple columns.
24. Concurrency
Control (Concurrency Control): a dbms service that executes multiple 15th Five-Year Plan and ensures data integrity in a multi-user environment.
25.
Constraint: the database does not allow consistency rules that contain error data.
26. Data Conversion and
Loading (data conversion and loading): a stage in which the lifecycle of a database application is heavy, including converting existing data to a new database, and converting offline applications to a new database.
27. Data
Dictionary (data dictionary): see system directory (system Catalog ).
28. Data
Independence (Data independence): Data Description of the application that uses data. This means that if a new data structure is added to the database or 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 modified part.
29.
Data Model: an integrated set that describes the concepts of data, inter-data relationships, and data constraints.
30. Data
Redundancy (data redundancy): see redundant data (redundant data ).
31. Data
Security (Data Security): includes access and use of database objects (such as tables and views) and operations that users can perform on these objects.
32.
Database: a collection of logically related data (and the description of the data), used to meet the company's information requirements.
33. Database
DESIGN: a stage in the lifecycle of a database application, including creating a database that supports company operations and objectives.
34. Database
Integrity: indicates the correctness and consistency of the stored data. Integrity is usually expressed by constraints.
35. Database Management
System, DBMS (database management system): a software system that allows users to define, create, and maintain databases and control database access.
36. Database
Planning (Database Planning): it can implement management activities at various stages of database applications as effectively as possible.
37. Database
Server (Database Server): Same server.
38. DBMS engine (DBMS engine): Same server.
39. DBMS
Selection (DBMS selection): a stage in the database application lifecycle, including selecting an appropriate DBMS to support database applications.
40. Degree of
Relationship: the number of entities involved in a link.
41.
Denormalization (denormalization): formally, This term refers to the modification of the basic table structure, so that the new table is less normalized than the original table. However, it can also be used to describe the situation of combining two tables into a new table, which has the same paradigm as the original table, but it contains more null values than the original table.
42.
Derived attribute (derived attribute): indicates the attribute whose value can be derived from a value of the relevant attribute and attribute set. This attribute is not required in the entity.
43. Design
Methodology (Design Methodology): a structured approach that uses processes, tools, and documents to support and simplify design processes.
44. disjoint
Constraint (no join constraint): describes the relationship between sub-class members and determines whether a member of a super-class can become one or more sub-class members.
45.
Domain: the value range of one or more attributes.
46. Entity (entity): a collection of objects of the same nature, which are identified by users or companies and can exist independently.
47.
Entity Integrity: In a basic table, the value of the primary key column cannot be empty.
48. Entity
Occurrence: a unique and identifiable object in an object.
49. entity-relationship
Model: The detailed logical representation of the company's entities, attributes, and relationships.
50.
Fact-finding: uses techniques such as interviews and questions to collect formal processes on system facts, requirements, and performance.
51. Fan
Trap, however, these two entities should have a direct relationship between them to provide necessary information.
52.
Field: tuple ).
53. File: A name set of related records stored in the sub-primary storage.
54. file-based
System (file-based system): a collection of files used to manage data in one or more files (create, insert, delete, update, and retrieve, and generate applications (usually reports) based on the data in these files ).
55.
File organization: the arrangement of records in files when files are stored on disks.
56. First Normal
Form (1nf, first paradigm): The intersection of each column in a table and records that contain the partition into a table that contains a value.
57. Foreign
Key (foreign key): a set of one or more columns in a table. These columns match the candidate keys in some (or possibly the same) tables.
58. 4gl, fourth-generation
Language (fourth-generation language): A non-procedural language, such as SQL, which only requires the user to define what operations must be done. 4gl is responsible for translating the operations into how to implement these operations.
59.
Full functional dependency (full function dependency): A column is functionally dependent on the composite primary key, but does not depend on the condition of any subset of the primary key.
60.
Functional dependency: describes the relationship between columns in a table.
61.
Generalization (generalization): The process of minimizing the differences between entities by identifying common features between entities.
62. Generalization
Hierarchy: type hierarchy ).
63. Global Data
Model (Global Data Model): a data model that represents the entire company (and a part of the company to be modeled.
64.
Implementation: a stage in the database application lifecycle, including physical implementation of database and application design.
65.
Index: a data structure that allows the DBMS to place a specific record in a file more quickly to accelerate the response to user queries.
66. Infomation
System: resources that can collect, manage, control, and distribute data/information across the company.
67.
Inheritance (inheritance): see attribute inheritance ).
68. Integrity
Constaints (integrity constraints): prevents data inconsistency constraints in the database.
69. IS-A
Hierarchy (IS-A hierarchy): type hierarchy ).
70. Local Logical Data
Model: A data model that represents a combination of a specific user view or user view.
71. logical database
Design (logical database design): the process of building a company's data model based on a specific data model, but does not rely on a specific DBMS and other physical conditions.
72.
Meta-data (metadata): For data, see the system directory (system Catalog ).
73. Mision
Objective: identifies a specific task that a database must support.
74. Mission
Statement: defines the main objectives of database applications.
75.
Multiplicity (diversity): defines the number of occurrences of entities associated with one occurrence of a related entity.
76. multi-valued
Attribute (multi-value attribute): an attribute that stores multiple values for an object.
77. nonkey
Attribute/column (non-key attribute/column): attribute/column that is not part of the key.
78. Normal
Forms: a stage of the standardization process. The first three paradigms are 1nf, 2nf, and 3nf respectively ).
79.
Normalization (normalization): a technology that produces features that meet the needs of users and companies.
80.
Null: the value of a column that is unknown or unavailable for this record.
81. Operational
Maintenance (operation and maintenance): a stage of the database application lifecycle, including monitoring and maintaining the running of the system after installation.
82. Participant
Constraint (Participation constraint, EER model): determines whether each occurrence of a superclass must be involved as a member of the subclass.
83. Participant
Constraint (involved constraint, ER Model): determines whether all or only some entities are involved in the link.
84. Physical Database
Design (physical database design): the process of generating the description of the Database implementation on the secondary storage, it describes the basic tables, the organization of files, the indexes used for obtaining valid access, and all descriptions related to integrity constraints and security restrictions.
85.
Primary Index: The index built on the sorted key field of the file. A file can have at most one primary index or one cluster index.
86. Primary
Key (master key, ER Model): used to identify the candidate keys that appear for each object.
87. Primary
Key (master key, relational model): used to identify the candidate key for record uniqueness in a table.
88.
Privileges: allows you to perform operations on a given basic table and view.
89.
Prototyping: a stage in the life cycle of the database application, including the workflow model of the database application.
90.
Query-by-example (QBE): A non-procedural database language for relational DBMS. QBE is a graphical "point-by" Method for querying databases.
91.
RDBMS: relational DBMS.
92. Record: Same as the metadata group (tuple ).
93. Recovery
Control: Restore the database to the correct state.
94. rcursive
Relationship: a link that blocks the same entity from multiple times in different roles. For example, staff supervises
Staff.
95. redundant data (redundant data): duplicate data stored in multiple tables.
96. referential
Integrity: if an external key exists in a table, the external key value must match the value of the candidate key for some records in the master table.
97.
Relation: A link is a table with columns and rows.
98. Relational
Model: A data model that represents data in the form of tables (or relationships.
99. Relational
Database (Relational Database): a set of standardized tables.
100. Relation: a meaningful relationship between entities.
101. Relationship
Occurrence: a unique and identifiable relationship between two entities.
102. Requirements collection and
Analysis: a stage in the lifecycle of a database application, including collecting and analyzing information about the company to be supported by database applications, this information is used to identify new database application requirements.
103.
Row: Same as the metagroup (tuple ).
104. Second normal
Form (second paradigm): a table that is already the first paradigm, and satisfying all non-primary key columns can only be obtained from all the columns that constitute the primary key.
105. Secondary
Index (secondary index): The index defined on the non-Ordered Field of the data file.
106.
Security: prevents unauthorized users from accessing the database, including intentionally or unintentionally. RDBMS usually provides two types of security: data security and system security.
107.
Server: the software application that provides services to the requesting customers. See the two-tier/three-tier client-server architecture.
108. Simple
Attribute (simple attribute): Only the attributes of one component.
109. single-valued
Attribute: an attribute with only one value for an object.
110.
Specialization.
111. Specialization
Hierarchy: type hierarchy ).
112. SQL (Structured Query
Language (Structured Query Language): A non-procedural database language for RDBMS. In other words, you only need to specify the information you need, instead of how to obtain the information.
SQL has been standardized by the International Organization for Standardization (ISO). Therefore, SQL is the formal and actual standard language for defining and manipulating RDBMS.
113. Strong
Entity (strong entity): An entity that does not depend on the existence of the primary keys of other entities.
114.
Subclass (subclass): an object that appears in a (superclass) object and maintains specific attributes and relationships and has different roles.
115.
Superclass: indicates all objects in the object that store public attributes and links. For more information, see special and general.
116.
Superkey (superkey, ER Model): an attribute or attribute set, which identifies the appearance of each entity.
117.
Superkey (relational model): a column or column set uniquely identifies a record in a table.
118. System
Catalog (system directory): stores data about the database structure, user, application, and other information.
119. System
Definition (system definition): a stage in which the database application declares a heavy cycle, including defining the database application and its main user views and boundaries.
120. System
Security (System Security): It is inferior to the user name and password to protect the access and use of databases at the system level.
121. Table: relation ).
122.
Ternary relationship: the relationship between three entities. For example, the registers relationship between panch, staff, and member.
123.
Testing (TEST): a stage of the database application lifecycle, including executing the application and intentionally discovering errors.
124. Third normal
Form, 3nf (third paradigm): a table that already has 1nf and 2nf, and the values of all non-primary columns can only be obtained from the primary key column, it cannot be obtained from other columns.
125. 3gl,
Third-generation
Language (third-generation language): A Procedural language, such as COBOL, C, and C ++. It requires users (usually programmers) to specify what must be done and how to do these things.
126.
Three-tier client-server
Architecture (layer-3 client-server architecture): a database server is used to run a DBMS, which is composed of a client that processes user interfaces, an application server that processes business logic, and an application server that processes data.
127.
Top-down
Approach (top-down method for database design): A design method that begins with defining the main structure of the system, and then gradually splits these structures into smaller units. In the database design, start the top-level step by identifying the relationship between the object and the data, and then gradually add details, such as the information about the object and the link you want to save (as an attribute) and all constraints on entities, relationships, and attributes.
128.
Transaction: an action or a series of actions executed by users and applications to access or modify the database content.
129. Transaction
Processing
Monitor, TPM (Transaction Processing monitor): a program that controls data key conversion between the client and the server to provide a consistent environment for online transaction processing (OLTP.
130.
Transitive
Dependency: Assume that A, B, and C are columns in the table. If B depends on a (A --> B ), and C depends on B (B --> C), C passes through B and depends on a (assuming a does not depend on B or C ). If a transfer dependency exists on the primary key, this table is not 3nf. Dependencies must be removed from the table to meet the 3nf requirement.
131.
Tuple (tuples): a record in a link.
132. two-tier client-server
Architecture (two-layer client-server architecture): consists of the main business and data processing logic, as well as client applications with user interfaces, and server programs that manage and control database access.
133.
Type hierarchy (type hierarchy): one is to mention its sub-classes and their superclasses, and so on.
134. UML (uniied Modeling
Language, Unified Modeling Language): a new method that introduced many Object-Oriented Analysis and Design Methods in 1980s and 1990s.
135. Update
Anomalies (update exception): the possible inconsistency when the user view updates an identifier containing redundant data. There are three types of exceptions: insert, delete, and update.
136. User
View (User View): The needs of database applications defined from a specific job (such as a manager or manager) or business application field (such as market, employee, or inventory control.
137.
View: A "virtual base table" that does not actually exist in the database, but is generated by the DBMS from the basic tables it involves.
138. View Integration
Approach (view Synthesis Method for database design): the requirement of each user view to build an independent data model that represents the user's attempt to use. In the database design stage, the result database model is merged into a larger model.
