702. UNDERSTANDING OF DATABASE DESIGN
Text
could be a coded value - assign to an integer through a domain
BLOBs
data stored as a long sequence of binary numbers - ArcGIS stores annotation and dimensions as BLOBs - images, multimedia, bits of code
Double
double-precision floating-point numbers
Physical database design
o Physical configuration of the database on the storage media o Detailed specification of data elements, data types, indexing options, and other parameters residing in the DBMS data dictionary o Modules, hardware, software
Geometry
point, line, polygon, multipoint, multipatch.
Database design
process of producing a detailed data model of a database.
Raster field types
raster can be stored within the geodatabase.
Float
single-precision floating-point numbers
Field Types
the proper field type will secure data and make databases more efficient.
Specify Primary Keys and Analyze Relationships
• Choose a primary key for each feature class and table (a unique identifier). • Define relationships (one-to-one, one-to-many, many-to-many) between tables.
Document the Database Design
• Create a data dictionary describing each table, field, and relationship. • Document any business rules or assumptions.
Implement the Database
• Create the actual database using a Database Management System (DBMS). • Set up tables, relationships, views, and indexes. • Prepare for backups and disaster recovery.
Create Views and Indexes
• Create views to simplify complex queries or restrict access to sensitive data. • Define indexes to improve query performance.
Design the Feature Classes, Tables and Fields
• Determine what features need to be captured, stored and what type of geometry is required (points, lines, polygons, images etc.). Will features need to be modeled for different scales? • Determine the data types for each field (e.g., text, number, date). • Set any constraints (such as required fields or unique values). • Identify coded value domains.
Divide the Information into Feature Classes and Tables
• Each feature class or table represents an entity or a relationship between entities. • Tables should be normalized to minimize redundancy and improve data integrity.
Logical Data Model
Arrange data in a logical structure that can be mapped into the storage objects supported by the database management system.
Global Identifiers
Global ID and GUID - data types store registry style strings consisting of 36 characters enclosed in curly brackets.
Find and Organize the Information Required
• Gather all the types of information you want to record in the database. • Identify the entities (objects or concepts) relevant to your domain. • Define the attributes (fields) for each entity.
Test and Refine the Design
• Populate the feature classes, tables with sample data. • Test queries, views, and data manipulation operations. • Refine the design based on feedback and testing.
Implement Data Integrity and Security Measures
• Set up constraints (such as foreign keys) to maintain data integrity. • Define security rules to control access to data. • Determine if versioning is required.
Determine the Purpose of Your Database
• Understand the goals and requirements for your database. • Consider the users, data sources, and anticipated queries.
Long integer
between -2,147,483,648 and 2147483647
Short integer
between -32768 and 32768
Object Identifiers
Unique IDs and FIDs
Dates
a calendar date and sometimes a time is associated.
What is the full form of DBMS? A) Data of a Binary Management System B) Database Management System C) Database Management Service D) Data Backup Management System
b) Database Management System
Design process
Conceptual schema, Logical Data Model, Physical database design
Conceptual schema
Determine where relationships and dependency are within the data.
