|
순서 |
명칭 (Oracle Insights) |
해설 (Oracle Insights) |
설명 (Wikipedia) |
Rule 1 |
The Information Rule |
테이블(Relations), 컬럼은 직관적이어야함 |
All information in a relational data base is represented explicitly at the logical level and in exactly one way — by values in table |
Rule 2 |
The Guaranteed Access Rule |
테이블의 데이터는 PK, 컬럼명 등으로 쉽게 접근할 수 있어야
함 |
Each and every data (atomic value) in a relational data base is guaranteed to be logically accessible by resorting to a combination of table name, primary key value and column name |
Rule 3 |
Systematic Treatment of Null Values |
Null이 존재해야 함 |
Null values (distinct from the empty character string or a string of blank characters and distinct from zero or any other number) are supported in fully relational DBMS for representing missing information and inapplicable information in a systematic way, independent of data type. |
Rule 4 |
Dynamic On-Line Catalog |
데이터 구조를 실시간으로 확인할 수 있는 데이터 딕셔너리가 존재해야 함 |
The data base description is represented at the logical level in the same way as ordinary data, so that authorized users can apply the same relational language to its interrogation as they apply to the regular data. |
Rule 5 |
Comprehensive Data Sublanguage |
데이터를 다룰 수 있는 언어(SQL)의 필요 |
A relational system may support several
languages and various modes of terminal use (for example, the
fill-in-the-blanks mode). However, there must be at least one language whose
statements are expressible, per some well-defined syntax, as character
strings and that is comprehensive in supporting all of the following items: |
Rule 6 |
View Updating Rule |
Update가 가능한 구조로된 View는 Update할
수 있어야 함 |
All views that are theoretically updatable are also updatable by the system |
Rule 7 |
High-level Insert, Update, and Delete |
SQL의 조회(Query) 기능이 Insert, Update,
Delete에도 가능해야 함 |
The capability of handling a base relation or a derived relation as a single operand applies not only to the retrieval of data but also to the insertion, update and deletion of data. |
Rule 8 |
Physical Data Independence |
사용자의 프로그램이 데이터베이스의 물리적구조에 영향을 받아선 안된다 |
Application programs and terminal activities remain logically unimpaired whenever any changes are made in either storage representations or access methods. |
Rule 9 |
Logical Data Independence |
테이블 변경 등의 데이터 구조 변경에 의해 사용자의 뷰가 영향 받아선 안된다 |
Application programs and terminal activities remain logically unimpaired when information-preserving changes of any kind that theoretically permit unimpairment are made to the base tables. |
Rule 10 |
Integrity Independence |
무결성제약이 데이터베이스에서 가능해야 함 |
Integrity constraints specific to a particular relational data base must be definable in the relational data sublanguage and storable in the catalog, not in the application programs |
Rule 11 |
Distribution Independence |
분산 트랜잭션 가능 |
A relational DBMS has distribution independence. |
Rule 12 |
Nonsubversion Rule |
관계형 데이터베이스는 백도어가 없어야 한다(현재까지도 논란이
있음) |
If a relational system has a low-level (single-record-at-a-time) language, that low level cannot be used to subvert or bypass the integrity rules and constraints expressed in the higher level relational language (multiple-records-at-a-time). |