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Database Design Specialist. Lesson 1: Introduction to Databases. Objectives. List database types (e.g., flat file, relational), and identify their uses and architectures Describe the types of database management system (DBMS), and explain the benefits and limitations of each DBMS type
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Objectives • List database types (e.g., flat file, relational), and identify their uses and architectures • Describe the types of database management system (DBMS), and explain the benefits and limitations of each DBMS type • Analyze and select appropriate database designs, and identify the solution that addresses the application needs
What Is a Database? • File-based databases • Flat-file databases • The evolution of databases
Relational Databases and DBMSs • Relational databases • Structured Query Language • Database administrator • Advantages and disadvantages of DBMSs • Choosing the correct database type
The Origins of Relational Databases • Codd first proposed the relational data model in 1970 • System R • Development of SQL • INGRES • IBM UK Scientific Center
Summary • List database types (e.g., flat file, relational), and identify their uses and architectures • Describe the types of database management system (DBMS), and explain the benefits and limitations of each DBMS type • Analyze and select appropriate database designs, and identify the solution that addresses the application needs
Objectives • Define common database architectures (e.g., single, multi-tier) • Describe the function of Structured Query Language (SQL), including language subsets • Describe the function of Data Definition Language (DDL) • Describe the function of Data Manipulation Language (DML)
Objectives (cont’d) • Describe the function of Data Control Language (DCL) • Define essential database concepts and terms, including relation, relation name, table, row, column, value, relational algebra, data modeling, data relationship • Explain the concepts of attribute, degree, tuple and cardinality
Objectives (cont’d) • Define entities, including strong entities, weak entities • List characteristics of relations (e.g., column characteristics, row characteristics) • Describe table types (e.g., base tables, virtual tables) • Distinguish between primary and foreign keys, including null value, composite key • Explain data models in relational databases
Objectives (cont’d) • Describe common database relationships (e.g., one to one, one to many, many to many) and identify the notation for such relationships (e.g., 1:n) • Define relational integrity concepts, including domain constraints, entity and referential integrity views • Explain the structure and purpose of a data dictionary
Multitier Database Architecture • Two-tier client-server architecture • Fat client • Three-tier client-server architecture • Thin client • n-tier architecture
Relational data structure Rows (tuples) Columns (attributes) Domains Degrees Cardinality Normalization Relational Model Terminology
Using Tables to Represent Data • Entities • Characteristics of relations • Types of tables • Primary keys • Foreign keys
Data Models • Components • Structural information • Manipulative information • Integrity information
Entities and Data Relationships • Entity-relationship (ER) modeling • Strong entities • Weak entities
Relational Integrity • Domain constraints • Entity integrity • Referential integrity • Views
Database Languages • Data Definition Language • Data Manipulation Language • Data Control Language • Data dictionaries
Summary • Define common database architectures (e.g., single, multi-tier) • Describe the function of Structured Query Language (SQL), including language subsets • Describe the function of Data Definition Language (DDL) • Describe the function of Data Manipulation Language (DML)
Summary (cont’d) • Describe the function of Data Control Language (DCL) • Define essential database concepts and terms, including relation, relation name, table, row, column, value, relational algebra, data modeling, data relationship • Explain the concepts of attribute, degree, tuple and cardinality
Summary (cont’d) • Define entities, including strong entities, weak entities • List characteristics of relations (e.g., column characteristics, row characteristics) • Describe table types (e.g., base tables, virtual tables) • Distinguish between primary and foreign keys, including null value, composite key • Explain data models in relational databases
Summary (cont’d) • Describe common database relationships (e.g., one to one, one to many, many to many) and identify the notation for such relationships (e.g., 1:n) • Define relational integrity concepts, including domain constraints, entity and referential integrity views • Explain the structure and purpose of a data dictionary
Objectives • Describe the elements of a database planning strategy (e.g., defining the scope of a database application) • List the necessary steps for creating a database requirements document, including conducting interviews, noting project constraints, identifying the precise duties of the database, creating a database design document
Objectives (cont’d) • Explain the importance of data modeling and entity relationship diagrams during the planning stage (e.g., define the concept of an entity-relationship [ER] diagram) • Create a database prototype • Describe the purpose of database application testing, including white-box testing, black-box testing
Objectives (cont’d) • List the criteria for selecting a database management system and an application interface • Describe database design steps, including determining the proper steps in creating entities, applying normalization, selecting a database management system (DBMS)
Create a database strategy Define database application scope Create a database requirements document Design the database Select a DBMS Design the database application Create database prototypes Test the database application Implement the database application Convert legacy data Maintain the database Database Design Life Cycle
Database Requirements Document • Conducting interviews • Requirements document information
Selecting a DBMS • Selection criteria • Data definition functionality • Physical criteria • Access criteria • Transactions • Utilities • Development tools • Miscellaneous features
GUI considerations Descriptive page titles Clear instructions Consistent grouping of input fields Logically labeled fields Consistent color use Properly sized data entry fields Logical cursor movement Error messages Clearly indicated optional fields Completion message Selecting an Application Interface
Summary • Describe the elements of a database planning strategy (e.g., defining the scope of a database application) • List the necessary steps for creating a database requirements document, including conducting interviews, noting project constraints, identifying the precise duties of the database, creating a database design document
Summary (cont’d) • Explain the importance of data modeling and entity relationship diagrams during the planning stage (e.g., define the concept of an entity-relationship [ER] diagram) • Create a database prototype • Describe the purpose of database application testing, including white-box testing, black-box testing
Summary (cont’d) • List the criteria for selecting a database management system and an application interface • Describe database design steps, including determining the proper steps in creating entities, applying normalization, selecting a database management system (DBMS)
Objectives • List the steps of the conceptual design phase (e.g., identifying entities, attribute domains, relationships) • Describe how to identify entities • List ways to identify attributes and attribute domains for entities
Objectives (cont’d) • List ways to identify candidate and primary keys for entities • Identify and determine data relationships • Create an entity-relationship (ER) diagram • Analyze an entity-relationship (ER) diagram or model to determine relation types
Objectives (cont’d) • Define and describe domains • Explain the results of poor database design, and describe insertion, deletion and update anomalies in databases • Describe database design steps, including determining the proper steps in creating entities, applying normalization, selecting a database management system (DBMS)
Effects of Poor Database Design • Insertion anomalies • Deletion anomalies • Update anomalies
Database Design Phases • Conceptual phase • Logical phase • Physical phase
Conceptual Database Design • Identifying entities • Identifying attributes and attribute domains for entities • Identifying relationships • Identifying candidate and primary keys for entities • Creating an entity-relationship (ER) diagram • Reviewing the ER model by the user and design team
Entity-Relationship Models • Creating ER models • Defining domains • Common SQL data types • Determining data relationships • Recursive relationships
Summary • List the steps of the conceptual design phase (e.g., identifying entities, attribute domains, relationships) • Describe how to identify entities • List ways to identify attributes and attribute domains for entities
Summary (cont’d) • List ways to identify candidate and primary keys for entities • Identify and determine data relationships • Create an entity-relationship (ER) diagram • Analyze an entity-relationship (ER) diagram or model to determine relation types
Summary (cont’d) • Define and describe domains • Explain the results of poor database design, and describe insertion, deletion and update anomalies in databases • Describe database design steps, including determining the proper steps in creating entities, applying normalization, selecting a database management system (DBMS)
Objectives • Distinguish between specific normal forms, including first normal form (1NF), second normal form (2NF), third normal form (3NF), Boyce-Codd normal form (BCNF) • Describe the normalization process • Define and explain determinant, decomposition and functional dependency
Objectives (cont’d) • Describe database design steps, including determining the proper steps in creating entities, applying normalization, selecting a database management system (DBMS)
What Is Normalization? • Normal forms • First normal form • First normal form anomalies • Second normal form • Second normal form anomalies • Third normal form • Boyce-Codd normal form
Related Concepts • Decomposition • Atomic value • Partial functional dependency • Transitive dependency • Denormalization