#### PostgreSQL DBA Roadmap ##### Learn basic RDBMS terms and concepts Get basic understanding of Postgres key terms and basic RDBMS concepts. - Object model: data types, columns, rows, tables, schemas, databases, queries. - Relational model: domains, attributes, tuples, relations, constraints, NULL. - Databases high-level concepts: ACID, MVCC, transactions, write-ahead log, query processing. - Links: - [Postgres Glossary](https://www.postgresql.org/docs/13/glossary.html) - SQL and Relational Theory - Christopher J. Date, 2009 - Database Design and Relational Theory - Christopher J. Date, 2012 ##### Learn how to install and run PostgreSQL Get practical skills of how to set up and run Postgres to get a working environment for further learning. - using package managers (APT, YUM, etc.) - using `Docker`. - managing Postgres service using `systemd` (start, stop, restart, reload). - managing Postgres service using `pg_ctl`, or OS-specific tools (like `pg_ctlcluster`). - connect to Postgres using `psql`. - deploy database service in cloud environment (AWS, GCE, Azure, Heroku, DigitalOcean, etc...). - Links: - [Official download and install instructions](https://www.postgresql.org/download/) - [Official Docker images](https://hub.docker.com/_/postgres) ##### Learn SQL concepts Get practical skills of how to create and manipulate database objects and how to execute queries using `psql` client. - Understanding basic data types. - DML queries: querying data, modifying data, filtering data, joining tables. - advanced topics: transactions, CTE, subqueries, lateral join, grouping, set operations. - DDL queries: managing tables and schemas (create, alter, drop). - Import and export data using `COPY`. - Links: - [DB Fiddle](https://www.db-fiddle.com/) - [PostgreSQL Tutorial](https://www.postgresqltutorial.com/) - [PostgreSQL SQL Getting Started](https://www.postgresql.org/docs/current/tutorial-sql.html) - [The SQL Language](https://www.postgresql.org/docs/current/sql.html) ##### Learn how to configure Postgres Get understanding of the main aspects of how Postgres could be configured. Deep understanding of Postgres internals is not yet necessary here. - postgresql.conf: - resources usage - write-ahead log - checkpoints and background writer - cost-based vacuum and autovacuum - replication - query planner - reporting, logging and statistics - adding extra extensions - ... keep exploring other configuration options Links: - [Postgresqlco.nf](http://postgresqlco.nf/) ##### Learn Postgres security concepts Get understanding about basic security concepts and common ways of how to deploy secure configurations. - Authentication models, roles, pg_hba.conf, SSL settings. - Objects privileges: grant/revoke, default privileges. - Advanced topics - row-level security, selinux. - Links: - [Client authentication](https://www.postgresql.org/docs/current/client-authentication.html) - [Roles and users managements](https://www.postgresql.org/docs/current/user-manag.html) ##### Develop infrastructure DBA skills Get practical skills of how to deploy, extend, maintain and support Postgres installations and 3rd-party Postgres ecosystem software. - Replication: streaming replication, logical replication - Backup/recovery tools: - Built-in: `pg_dump`, `pg_dumpall`, `pg_restore`, `pg_basebackup` - 3rd-party: `barman`, `pgbackrest`, `pg_probackup`, `WAL-G` - Backup validation procedures - Upgrading procedures - minor and major upgrades using `pg_upgrade` - upgrades using logical replication - Connection pooling: - `Pgbouncer` - alternatives: `Pgpool-II`, `Odyssey`, `Pgagroal` - Infrastructure monitoring: `Prometheus`, `Zabbix`, other favourite monitoring solution - High availability and cluster management tools: - `Patroni` - alternatives: `Repmgr`, `Stolon`, `pg_auto_failover`, `PAF` - Applications Load Balancing and Service Discovery: `Haproxy`, `Keepalived`, `Consul`, `Etcd` - Deploy Postgres on `Kubernetes`: simple `StatefulSet` setup, `HELM`, operators - Resource usage and provisioning, capacity planning ##### Learn how to automate routines Get practical skills, learn automation tools and automate existing routine tasks. - Automation using shell scripts or any other favourite language (`Bash`, `Python`, `Perl`, etc) - Configuration management: `Ansible`, `Salt`, `Chef`, `Puppet` ##### Develop application DBA skills Learn theory and get practical skills of how applications should work with Postgres - Migrations: - practical patterns and antipatterns - tools: `liquibase`, `sqitch`, language-specific tools - Data import/export, bulk loading and processing - Queues: - practical patterns and anti-patterns - `Skytools PGQ` - Data partitioning and sharding patterns. - Database normalization and normal forms. - Books: - The Art of PostgreSQL - Dimitri Fontaine, 2020 ##### Learn Postgres advanced topics Here is important to continuously extend and develop existing knowledge about Postgres. - Low level internals: - Processes and memory architecture - Vacuum processing - Buffer management - Lock management - [Physical storage and file layout](https://www.postgresql.org/docs/current/storage.html) - [System catalog](https://www.postgresql.org/docs/current/catalogs.html) - Fine-grained tuning: - Per-user, per-database settings - [Storage parameters](https://www.postgresql.org/docs/current/sql-createtable.html#SQL-CREATETABLE-STORAGE-PARAMETERS) - Workload-dependant tuning: OLTP, OLAP, HTAP - Advanced SQL topics: - PL/pgSQL, procedures and functions, triggers - aggregate and window functions - recursive CTE - Links: - [The Internals of PostgreSQL](http://www.interdb.jp/pg/index.html) for database administrators and system developers - [PL/pgSQL Guide](https://www.postgresql.org/docs/current/plpgsql.html) ##### Learn Postgres troubleshooting technics Get basic understanding about troubleshooting tools and get practical skills of how to detect and resolve problems. - Operating system tools - `top` (`htop`, `atop`) - `sysstat` - `iotop` - Postgres system views - `pg_stat_activity` - `pg_stat_statements` - Postgres tools - `pgcenter` - *personal recommendation* - Query analyzing: - [EXPLAIN](https://www.postgresql.org/docs/current/sql-explain.html) - [Depesz](https://explain.depesz.com/) online EXPLAIN visualization tool - [PEV](https://tatiyants.com/pev/#/plans) online EXPLAIN visualization tool - [Tensor](https://explain.tensor.ru/) online EXPLAIN visualization tool, RU language only - Log analyzing: - `pgBadger` - Ad-hoc analyzing using `grep`, `awk`, `sed`, etc. - External tracing/profiling tools: `gdb`, `strace`, `perf-tools`, `ebpf`, core dumps - Troubleshooting methods: USE, RED, Golden signals - Links: - [Linux Performance](http://www.brendangregg.com/linuxperf.html) by Brendan Gregg - [USE Method](http://www.brendangregg.com/usemethod.html) ##### Learn SQL optimization technics Get understanding and practical skills of how to optimize SQL queries. - Indexes, and their use cases: B-tree, Hash, GiST, SP-GiST, GIN, BRIN - SQL queries patterns and anti-patterns - SQL schema design patterns and anti-patterns - Links: - [Use the Index, Luke](https://use-the-index-luke.com/) - a Guide to Database Performance for Developers - Books: - SQL Antipatterns: Avoiding the Pitfalls of Database Programming - Bill Karwin, 2010 ##### Develop architect skills Get deeper understanding of Postgres use cases and where Postgres is suitable and where is not. - Postgres forks and extensions: `Greenplum`, `Timescaledb`, `Citus`, `Postgres-XL`, etc. - RDBMS in general, benefits and limitations - Differences between Postgres and other RDBMS and NoSQL databases ##### Develop Postgres hacker skills Get involved to Postgres community and contribute to Postgres; be a useful member of Postgres, and the open source community; use personal experience to help other people. - daily reading and answering in [mailing lists](https://www.postgresql.org/list/) - pgsql-general - pgsql-admin - pgsql-performance - pgsql-hackers - pgsql-bugs - reviewing patches - writing patches, attending in [Commitfests](https://commitfest.postgresql.org/)