AWS Classroom notes 22/Jan/2024

Databases

• Relational Database:
  • Design:
    • In the form of tables with colums
    • Structure of database is called as schema
    • Each table will have columns and there will be relations between tables
  • Database Engine: This is a software implementation of databases.
    • Examples:
      • Oracle
      • Microsoft SQL Server
      • mySQL
      • PostgreSQL
      • IBM DB2
  • SQL (Structured Query Language): To create, retrieve, update and delete records of data there is a specification called as SQL Refer Here
  • Each vendor implements this SQL
    • Oracle => pl/sql
    • Microsoft SQL Server => t-sql
  • Each implementation will have datatypes (same or different) and query syntaxes
  • Indexes: To increase query times databases have indexes. There are two types of indexes
    • Primary index:
    • Secondary index:
  • if the column doesnot have index, then queries lead to full table scans
  • Administrative Activities:
    • Performance Tuning of Queries
    • Creating Replicas
    • Backups and restorations
    • Patching
• How can cloud help here?
  • Database as a service
  • no installations required (server side)
  • Administrative activities simplified or automated
    • Backups can be automated
    • simplified replications
    • Patching simplified
  • One activity where we still require DB expert is Performance tuning, AWS can give reports.
• AWS Relational Database engines
  • Oracle
  • Microsoft SQL Server
  • mysql
  • postgres
  • Aurora:
    • mysql
    • postgres