Technical Interview Bank & Deep-Dive Model Answers
DBA Technical Interview Questions
Curated technical interview questions covering MVCC, locking semantics, TempDB contention, and backup strategies with architectural model answers.
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PostgreSQLmid
CPU utilization on a production database suddenly spikes to 100%, and incoming connections begin timing out. What tools and system views do you use to diagnose and mitigate the root cause?
PostgreSQLjunior
In terms of physical versus logical operations, what is the difference between pg_dump and WAL-based physical backups (such as pg_basebackup)?
PostgreSQLsenior
What is the exact difference between VACUUM and VACUUM FULL in PostgreSQL, and how is Transaction ID Wraparound managed?
MySQLmid
What is the default Transaction Isolation Level in MySQL InnoDB and how does it prevent Phantom Reads?
SQL Serversenior
How do you diagnose and architecturally resolve TempDB contention (PFS/GAM/SGAM page latch waits) in SQL Server?
SQL Servermid
What is Parameter Sniffing in SQL Server, how does it cause sudden performance regressions, and what are the best remediation patterns?
SQL Serversenior