Database-Management-System
August 29, 2024Database-Management-System
August 29, 2024Database-Management-System
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Question 693
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Conceptual level, Internal level and external level are three components of the three level RDBMS architecture Which of the following is not a part of the conceptual level?
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Storage dependent details
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Entities,attributes and relationships
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Constraints
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Semantic information
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Question 693 Explanation:
Three levels of database architecture:
1. Physical Level
2. Conceptual Level
3. External Level
→ Mapping is the process of transforming request response between various database levels of architecture.
→ Mapping is not good for small database, because it takes more time.
→ In External / Conceptual mapping, DBMS transforms a request on an external schema against the conceptual schema.
→ In Conceptual / Internal mapping, it is necessary to transform the request from the conceptual to internal levels.
1. Physical Level
Physical level describes the physical storage structure of data in database.It is also known as Internal Level. This level is very close to physical storage of data. At lowest level, it is stored in the form of bits with the physical addresses on the secondary storage device. At highest level, it can be viewed in the form of files.The internal schema defines the various stored data types. It uses a physical data model.
2. Conceptual Level
Conceptual level describes the structure of the whole database for a group of users. It is also called as the data model. Conceptual schema is a representation of the entire content of the database. These schema contains all the information to build relevant external records. It hides the internal details of physical storage.
3. External Level
External level is related to the data which is viewed by individual end users. This level includes a no. of user views or external schemas. This level is closest to the user. External view describes the segment of the database that is required for a particular user group and hides the rest of the database from that user group.
1. Physical Level
2. Conceptual Level
3. External Level
→ Mapping is the process of transforming request response between various database levels of architecture.
→ Mapping is not good for small database, because it takes more time.
→ In External / Conceptual mapping, DBMS transforms a request on an external schema against the conceptual schema.
→ In Conceptual / Internal mapping, it is necessary to transform the request from the conceptual to internal levels.
1. Physical Level
Physical level describes the physical storage structure of data in database.It is also known as Internal Level. This level is very close to physical storage of data. At lowest level, it is stored in the form of bits with the physical addresses on the secondary storage device. At highest level, it can be viewed in the form of files.The internal schema defines the various stored data types. It uses a physical data model.
2. Conceptual Level
Conceptual level describes the structure of the whole database for a group of users. It is also called as the data model. Conceptual schema is a representation of the entire content of the database. These schema contains all the information to build relevant external records. It hides the internal details of physical storage.
3. External Level
External level is related to the data which is viewed by individual end users. This level includes a no. of user views or external schemas. This level is closest to the user. External view describes the segment of the database that is required for a particular user group and hides the rest of the database from that user group.
Correct Answer: A
Question 693 Explanation:
Three levels of database architecture:
1. Physical Level
2. Conceptual Level
3. External Level
→ Mapping is the process of transforming request response between various database levels of architecture.
→ Mapping is not good for small database, because it takes more time.
→ In External / Conceptual mapping, DBMS transforms a request on an external schema against the conceptual schema.
→ In Conceptual / Internal mapping, it is necessary to transform the request from the conceptual to internal levels.
1. Physical Level
Physical level describes the physical storage structure of data in database.It is also known as Internal Level. This level is very close to physical storage of data. At lowest level, it is stored in the form of bits with the physical addresses on the secondary storage device. At highest level, it can be viewed in the form of files.The internal schema defines the various stored data types. It uses a physical data model.
2. Conceptual Level
Conceptual level describes the structure of the whole database for a group of users. It is also called as the data model. Conceptual schema is a representation of the entire content of the database. These schema contains all the information to build relevant external records. It hides the internal details of physical storage.
3. External Level
External level is related to the data which is viewed by individual end users. This level includes a no. of user views or external schemas. This level is closest to the user. External view describes the segment of the database that is required for a particular user group and hides the rest of the database from that user group.
1. Physical Level
2. Conceptual Level
3. External Level
→ Mapping is the process of transforming request response between various database levels of architecture.
→ Mapping is not good for small database, because it takes more time.
→ In External / Conceptual mapping, DBMS transforms a request on an external schema against the conceptual schema.
→ In Conceptual / Internal mapping, it is necessary to transform the request from the conceptual to internal levels.
1. Physical Level
Physical level describes the physical storage structure of data in database.It is also known as Internal Level. This level is very close to physical storage of data. At lowest level, it is stored in the form of bits with the physical addresses on the secondary storage device. At highest level, it can be viewed in the form of files.The internal schema defines the various stored data types. It uses a physical data model.
2. Conceptual Level
Conceptual level describes the structure of the whole database for a group of users. It is also called as the data model. Conceptual schema is a representation of the entire content of the database. These schema contains all the information to build relevant external records. It hides the internal details of physical storage.
3. External Level
External level is related to the data which is viewed by individual end users. This level includes a no. of user views or external schemas. This level is closest to the user. External view describes the segment of the database that is required for a particular user group and hides the rest of the database from that user group.