My Oracle Services
I'm Mahmoud Darwish — Oracle ACE Apprentice and Senior DBA with hands-on experience across Exadata, ExaCS/ExaCC, RAC, Data Guard, GoldenGate, and OCI. Below is what I help teams with, whether it's a one-off engagement or a longer project.
Database Administration
Day-to-day DBA work across on-prem and cloud — the reliable plumbing behind any critical Oracle workload.
- 24×7 monitoring, alert tuning, proactive health checks
- Backup & recovery strategy with RMAN (catalog, cross-platform, PITR drills)
- Patching: RUs, one-off patches, Exadata bundle patches, zero-downtime rolling
- User, role, and privilege administration with audit hygiene
- Capacity planning, storage reclamation, growth forecasting
Database Migrations
Low-risk migration paths to the right target — I pick the approach based on your downtime budget, not on what's fashionable.
- On-prem → OCI (Base DB, ExaCS, ExaCC, Autonomous)
- DBCS → ExaCS consolidation and cost rightsizing
- Cross-platform and cross-endian migrations (AIX/HP-UX → Linux)
- Upgrades to 19c & 23ai (including PDB conversions)
- Zero Downtime Migration (ZDM), Data Pump, GoldenGate, XTTS
Performance & Health Check
A deep, evidence-based review of your database — not a generic checklist. You get a written report and a concrete action plan.
- AWR / ASH / ADDM interpretation for real workloads
- SQL tuning: plan analysis, SPM baselines, hint-free fixes
- Wait event analysis (I/O, concurrency, RAC GC, commit path)
- Memory sizing (SGA / PGA / In-Memory) and parameter review
- Statistics, partitioning, and index strategy recommendations
High Availability & DR
Architect and operate HA/DR stacks you can actually fail over — tested, documented, and owned by the team.
- Active Data Guard: physical, logical, cascaded, Far Sync
- Real Application Clusters (RAC) design & troubleshooting
- GoldenGate: bi-directional, active-active, zero-downtime upgrades
- Role transitions, DR drills, switchover / failover automation
- RPO / RTO alignment with business SLAs
Exadata, ExaCS & ExaCC
Engineered-systems-specific expertise — getting full value out of Smart Scan, storage cells, and IORM instead of treating Exadata like "just another server."
- Smart Scan / Storage Indexes / HCC compression tuning
- IORM policy design for multi-tenant workloads
- Exadata cell patching and rolling grid upgrades
- ExaCS / ExaCC provisioning, scaling, & OCPU management
- Migration from non-Exadata platforms with realistic benchmarks
Core Banking (T24) Tuning
Niche experience with Temenos T24 on Oracle — COB windows, end-of-day batches, and the very specific DB-side patterns these systems need.
- COB / EOD window reduction through targeted tuning
- Redo / undo sizing for high-concurrency banking workloads
- Online / offline reorgs without impacting settlement cut-offs
- Parameter & storage profile for T24 on Exadata & ExaCS
- Regulatory audit readiness (data retention, encryption, auditing)
Engagements range from a single AWR-based health check to multi-month migration programs. Send a short note about your environment and what you're trying to achieve — I'll reply with a scoped proposal.
Distilled.
Deep technical posts on Oracle performance, RAC, Exadata, and AI-assisted DBA workflows.