Topic
SQLAlchemy, Django ORM, transactions, relationship loading, connection pooling, migrations, and evidence-led SQL diagnosis.
Practice items tagged with Data Access & SQL.
Defines Django transaction nesting, exception boundaries, and post-commit work without promising durability.
Explains object identity, tracked changes, flush ordering, and the limits of session-level caching.
Chooses relationship loading from cardinality, query count, result size, and hidden-I/O boundaries.
Chooses atomic database expressions, row locks, and constraints from the invariant being protected.
Connects pool limits to process topology, transaction duration, database capacity, and queueing evidence.
Separates stale checkout protection, connection aging, pool waits, statement timeouts, and uncertain transactions.