Capgemini - Senior Database Engineer - PostgreSQL

PostgreSQL & SQL Excellence :

1. Minimum 6+ years of relevant experience in writing production-grade SQL using CTEs, window functions, and set-based processing.

2. Ensure SQL code is readable, testable, reusable, and version-controlled (peer-reviewed via PRs).

3. Optimise PostgreSQL performance through :

- Query tuning and execution plan analysis

- Indexing strategies

- Partitioning design and maintenance

- VACUUM/ANALYZE and table statistics management

- Locking and concurrency handling

4. Use EXPLAIN (ANALYZE, BUFFERS) to diagnose slow queries and interpret :

- Join strategies (nested loop, hash, merge)

- Sort methods

- Buffer hits vs reads (I/O hotspots)

5. Design effective indexes (btree, hash, GiST, GIN), including composite indexes aligned to filters, joins, and sort order

6. Apply index-friendly query patterns :