RDS Flashcards
What is RDS?
Relational Database Service. Used to complete online transaction processing (OLTP) . Pulling rows of data (frequently) or insert.
What RDS are available (6)?
SQLServer Oracle MySQLServer PostgreSQL Aurora MariaDB
What types of backups does RDS offer?
1) Automated Backups
2) DB Snapshot
What is the Retention Period of an RDS Automated Backup?
1-35 days
Describe an RDS Automated Backup
Takes a full daily snapshot and store logs throughout the day.
Recovery AWS chooses most recent daily backup and applies logs
Recovery is down to second w/ in retention period (Point int time recovery)
Default
Backups stored on s3 (free storage equal to size of DB)
Storage I/O may be suspended and may experience elevated latency during backup
Describe a DB Snapshot?
Manual backup initiated by a user
Stored after deleted RDS Instance (unlike automated backups)
Can you encrypt an RDS database?
Yes, encryption is done at rest using KMS.
But you cannot encrypt a currently existing DB
How to encrypt an existing DB?
Have to create a snapshot and encrypt that
What is Multi-AZ?
Host RDS in multiple availability zones for DISASTER RECOVERY.
Note this does nothing for performance.
What is Read Replica?
It is a way to scale out a DB load over multiple read replicas. Uses async replication from primary RDS to read replicas.
Use this on heavy read DB workloads.
Used for SCALING
Must have AUTO BACKUPS on in order to deploy read replica.
How many read replicas can you have?
5
Can you promote RR to become own DB?
Yes, but note this breaks replication
Which RDS Databases have RR capabilities?
MySQL
PostgreSQL
MariaDB
Aurora
What is Redshift?
Used for online analytics Processing (OLAP) Pulling a large number of records. Lots done in one query.
How to collect all SQL statements that take a long time to execute?
Enable slow query log in RDS
