PostgreSQL & MariaDB Databases
Database platforms are at the heart of many IT systems. I plan, install, and operate relational and document-based database systems with a focus on performance, security, high availability, and automation.
My technical focus is on PostgreSQL and MariaDB/MySQL, supplemented by MongoDB for document-oriented scenarios. I integrate databases into backup, monitoring, and CI/CD processes and provide technical and organizational support for migration projects—in particular, the switch from Oracle to PostgreSQL.
The focus is on reproducible setups, clear operating models, and a clean separation of development, test, and production environments. Architecture decisions are always made based on real workloads, maintenance requirements, and recovery objectives (RPO/RTO). This results in database platforms that are not only high-performing but also maintainable and operationally resilient in the long term.
Architecture & Installation
I plan database environments that combine stability, scalability, and traceability.
From single instances to cluster setups, I create structured systems with clearly defined roles and resources.
- Installation and operation of PostgreSQL, MariaDB/MySQL, MongoDB
- Architecture planning for standalone, master/slave, or cluster setups
- Storage design (ZFS, Ceph, LVM) and connection via iSCSI/NFS
- Automated installation with Ansible and cloud-init
- Documented parameter and tuning concepts
High availability & replication
I design databases with redundant architecture to enable downtime or maintenance windows without interrupting operations.
- Streaming replication, logical replication, hot standby
- Failover mechanisms via Patroni, Keepalived, or Corosync/Pacemaker
- Load balancing and read scaling
- Integration of PostgreSQL HA setups in Kubernetes (StatefulSets)
- Monitoring of replication status via Prometheus Exporter
Security & Access Control
I implement role-based access systems, encryption, and integrity checks to secure data and access.
- Role, schema, and rights management
- TLS encryption, SSL certificate management
- Authentication via LDAP, Kerberos, or PAM
- Encrypted backups and hash-secured dumps
- OpenSCAP and CIS-based security checks
Performance & Optimization
I analyze and optimize database performance based on real workloads and monitoring data.
- Query tuning with EXPLAIN / ANALYZE
- Index strategies, materialized views, partitioning
- Configuration tuning (work_mem, shared_buffers, autovacuum)
- I/O optimization, caching, connection pooling (pgBouncer, ProxySQL)
- Monitoring with pg_stat_statements, Prometheus Exporter, Grafana dashboards
Backup & Recovery
I develop and operate backup strategies using open-source tools that are functionally similar to enterprise solutions—without the licensing costs.
- BorgBackup, Restic, Bareos
- PITR (Point-in-Time Recovery) and incremental backups
- Automated dumps, snapshots, and recovery tests
- Versioned backup playbooks in Ansible
- Integration with Ceph/ZFS snapshots and Kubernetes Persistent Volumes
Migration & Integration
I support database migrations and integrations across different platforms, with a focus on open-source alternatives.
- Oracle > PostgreSQL migrations (via MapForce, pgloader, Python scripts)
- Data integration with ETL processes (Talend, Python, SQL scripts)
- Containerization of databases (Docker, K8s StatefulSets)
- Integration into CI/CD workflows for testing and schema updates
- Monitoring, logging, and alerting integrated into existing systems
Trainings
You can find specific trainings and current topics in the Comelio GmbH training catalog.
Available in-house at your company, as a webinar, or as an open training—designed to meet different requirements.
Frequently asked questions about PostgreSQL & MariaDB databases
In this FAQ, you will find the topics that come up most frequently in consultations and training sessions. Each answer is kept brief and refers to further content where necessary. Can’t find your question? Feel free to contact me.
Which database should I choose—PostgreSQL, MariaDB/MySQL, or MongoDB?
PostgreSQL for complex relations, MariaDB/MySQL for lean web workloads, MongoDB for flexible documents—each neatly integrated into monitoring, backup, and CI/CD.
How can I achieve high availability without downtime?
Replication + automatic failover (Patroni/Keepalived/Pacemaker) and read balancing; health checks and Prometheus/Grafana ensure operation, in Kubernetes via StatefulSets.
How do I ensure reliable backup and recovery?
Encrypted, versioned backups (Borg/Restic/Bareos), PITR, and regular restore tests; snapshots (ZFS/Ceph/K8s PVs) and playbooks ensure reproducible recovery.
How do I integrate databases cleanly into monitoring and alerting?
Specialized exporters (e.g., postgres_exporter, mysqld_exporter) are used to collect metrics such as latencies, locks, replication status, and resource consumption. In combination with Prometheus and Grafana, thresholds, trends, and early warnings can be reliably mapped.
What does professional database administration involve during ongoing operations?
Ongoing operations include monitoring, performance tuning, backup and recovery strategies, user and rights management, and regular maintenance. The goal is stable, secure, and traceable operation throughout the entire life cycle of the database.