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@ -1007,6 +1007,7 @@
- The instances of a potential subclass participate in a relationship unique to that subclass. - The instances of a potential subclass participate in a relationship unique to that subclass.
- DONE Designing databases - DONE Designing databases
- Understand Database Design Methodology #flashcard - Understand Database Design Methodology #flashcard
id:: 6489a99e-3ed0-4673-814d-f823e4998168
- Conceptual database design - Conceptual database design
- The process of constructing a model of the data used in an enterprise, independent of all physical considerations. - The process of constructing a model of the data used in an enterprise, independent of all physical considerations.
- Logical database design - Logical database design
@ -1014,6 +1015,7 @@
- Physical database design - Physical database design
- The process of producing a description of the implementation of the database (tailored to specific DBMS); - The process of producing a description of the implementation of the database (tailored to specific DBMS);
- general steps for Database Design Methodology. #flashcard - general steps for Database Design Methodology. #flashcard
id:: 6489a9b5-14ea-4b2b-bd47-07b93ae94124
- Gather requirements - Gather requirements
- Conceptual database design - Conceptual database design
- Logical database design - Logical database design
@ -1021,6 +1023,7 @@
- DONE SQL - DONE SQL
- purpose and importance of SQL. - purpose and importance of SQL.
- SQL is a transform-oriented language with 2 - SQL is a transform-oriented language with 2
id:: 6489c210-8ab6-4a38-979a-01af7618a3a4
collapsed:: true collapsed:: true
major components: #flashcard major components: #flashcard
- A DDL for defining database structure. - A DDL for defining database structure.
@ -1142,6 +1145,7 @@
- Fifth Normal Form (5NF): 5NF is the highest level of normalization and involves decomposing a table into smaller tables to _remove data redundancy and improve data integrity._ - Fifth Normal Form (5NF): 5NF is the highest level of normalization and involves decomposing a table into smaller tables to _remove data redundancy and improve data integrity._
- Anomaly - Anomaly
- Update Anomalies #flashcard - Update Anomalies #flashcard
id:: 6489a420-c0cb-4360-b34f-26a3a01ff46a
- Insertion anomalies - Insertion anomalies
- If there is a new row inserted in the table and it creates the - If there is a new row inserted in the table and it creates the
inconsistency in the table then it is called the insertion anomaly. For inconsistency in the table then it is called the insertion anomaly. For
@ -1191,6 +1195,7 @@
- Transaction Transparency: Ensures that all distributed transactions maintain distributed database’s integrity and consistency. - Transaction Transparency: Ensures that all distributed transactions maintain distributed database’s integrity and consistency.
- Performance Transparency: must perform as if it were a centralized DBMS. - Performance Transparency: must perform as if it were a centralized DBMS.
- DONE advantages and disadvantages of distributed databases #flashcard - DONE advantages and disadvantages of distributed databases #flashcard
id:: 6489c210-385e-483b-aa5c-dbe688c5f43b
- Advantages - Advantages
- Reflects organizational structure - Reflects organizational structure
- Improved shareability and local autonomy - Improved shareability and local autonomy
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3. Partition Tolerance → A query must have an answer, even if the system 3. Partition Tolerance → A query must have an answer, even if the system
is partitioned (unless there is a global failure). is partitioned (unless there is a global failure).
- BASE: #flashcard - BASE: #flashcard
id:: 6489dbd1-f9aa-47fa-8e9f-dfb2c73eff3c
- **Basically Available:** - **Basically Available:**
Instead of making it compulsory for immediate consistency, Instead of making it compulsory for immediate consistency,
BASE-modelled NoSQL databases will ensure the availability of data by BASE-modelled NoSQL databases will ensure the availability of data by