🔄 Module 25: Autonomous Database & Cloud Migration

CPU Auto-Scaling:
-- Monitor CPU consumption
-- Automatically scale up/down
-- No manual intervention needed
-- Scaling within subscription limits

Example: 4 OCPUs → Auto-scales to 16 OCPUs during peak
During off-peak → Scales back to 4 OCPUs

Phase 1: Assessment & Planning
├── Inventory existing databases
├── Identify dependencies
├── Performance baseline
└── Estimate effort & timeline

Phase 2: Design & Preparation
├── Target architecture design
├── Network connectivity planning
├── Security & compliance review
└── Capacity planning

Phase 3: Migration & Testing
├── Create target Autonomous DB
├── Data migration execution
├── Validation & reconciliation
└── Performance testing

Phase 4: Cutover & Optimization
├── Final data sync
├── Application cutover
├── Performance tuning
└── Production support

-- Full database export
expdp system/password@orcl DUMPFILE=full.dmp LOGFILE=full.log FULL=Y PARALLEL=4

-- Schema export
expdp system/password@orcl DUMPFILE=schema.dmp SCHEMAS=hr,oe PARALLEL=4

-- Import data
impdp system/password@orcl DUMPFILE=full.dmp LOGFILE=import.log PARALLEL=4

-- Network export (to cloud)
expdp system/password@orcl DUMPFILE=cloud.dmp NETWORK_LINK=to_adb PARALLEL=8

Source Database → Extract Process → Trail File → Pump Process → Network
↓
Replicat Process ← Trail File ← Target Database

Components:
- Extract: Captures source database transactions
- Pump: Transmits data over network
- Replicat: Applies transactions to target
- Trail: Binary transaction log

-- Create Extract (source capture)
ADD EXTRACT ex01, TRANLOG, BEGIN NOW
ADD EXTTRAIL ./dirdat/et EXTRACT ex01

-- Create Replicat (target apply)
ADD REPLICAT rp01 EXTTRAIL ./dirdat/et

-- Start processes
START EXTRACT ex01
START REPLICAT rp01

-- Monitor status
INFO ALL
STATUS EXTRACT ex01

-- Gather statistics (Auto in Autonomous DB)
EXEC DBMS_STATS.GATHER_SCHEMA_STATS('SCHEMA_NAME');

-- Check execution plans
EXPLAIN PLAN FOR SELECT * FROM table_name WHERE condition;
SELECT * FROM TABLE(DBMS_XPLAN.DISPLAY);

-- Monitor query performance
SELECT * FROM gv$sql_workarea WHERE module = 'YOUR_APP';

-- Identify slow queries
SELECT * FROM gv$sql WHERE executions > 100 AND elapsed_time > 1000000000;