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Study Note/SQL Developer license6

DML, TCL, DDL, DLC 1. Data Manipulation Language (DML):   - DML is used to manipulate data in a database, including querying, inserting, updating, and deleting data.   - Common DML commands include SELECT, INSERT, UPDATE, and DELETE.   - It allows users to interact with and manage data in the database.   - For example, the SELECT statement retrieves data from tables, INSERT inserts new records into a table, UPDATE.. 2024. 5. 7.
Transaction Transaction "transaction" refers to a concept representing a series of database operations. Transactions ensure the properties of atomicity, consistency, isolation, and durability (ACID) in the database, which are essential for managing data reliably and securely. Explanation of each ACID property: 1. Atomicity: All operations within a transaction must be treated as an indivisible unit, meaning .. 2024. 4. 22.
Normalization & Denormalization Normalization Normalization in data analysis refers to the process of organizing a database efficiently to reduce redundancy and improve data integrity and efficiency. The three stages of normalization—first normal form (1NF), second normal form (2NF), and third normal form (3NF)—each address specific types of data redundancy and dependencies. 1. First Normal Form (1NF): Ensures that each column.. 2024. 4. 22.
Waterfall Model & Agile Model Waterfall Model: Characteristics: The waterfall model follows a sequential and linear approach. Each phase must be completed before the next one begins. Key phases include requirements definition, design, implementation, testing, and maintenance. Advantages: Each phase is clearly defined, making it easy to track the progress of the project. It's easy to assess the impact of requirement or design.. 2024. 4. 17.
Importance of data modeling Ripple Effect: Data modeling plays a crucial role in minimizing the ripple effect of changes on the database. A well-designed data model reduces the impact of modifications to data structures on other parts of the system. For example, if changes are made to the attributes of one entity in the data model without affecting other entities, it reduces the effort required for system maintenance and u.. 2024. 4. 17.
Modeling In SQL, modeling refers to the process of designing and defining the structure of a database. It involves defining tables, columns, relationships, and constraints to meet the requirements of the database. Modeling in SQL typically includes the following elements: Conceptual Modeling: Conceptual modeling involves designing the overall structure of the database based on business requirements and c.. 2024. 4. 9.

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