NCM-DB case studies
NCM-DB · Put your knowledge to work in context.
NCM-DB is a professional certification for database administrators and engineers who need to demonstrate working competence across the full lifecycle of a database platform: designing it, installing and configuring it, organizing its storage and schema objects, writing and tuning SQL, protecting it through backup and high availability, monitoring its performance, and securing it through users, privileges, and auditing. It suits DBAs moving from task-level familiarity to end-to-end ownership, as well as developers and systems engineers whose work depends on a reliable database layer. The NCM-DB case studies are 6 cases and about 4,291 words.
1Consolidating 38 Databases onto Four Nodes
A retail company runs 38 departmental databases on 14 aging physical servers. Average CPU is 12%, but two servers are consistently at 75%.
716 words, about 4 min2New 19c Instance: Memory, Time Zone, and Listener Failures
A new production instance is being built on a virtual machine with 64GB RAM, 16 vCPUs, and a 200GB system disk. The installer configures MEMORY TARGET=40G.
696 words, about 3 min3Reclaiming a 1.6TB LOB Segment Under a Six-Hour Window
A 4.2TB OLTP schema contains a 1.6TB BASICFILE LOB segment in a dedicated tablespace with 8KB blocks and 1MB uniform extents. Over a year, 60% of the parent rows were deleted, but the LOB segment is still 1.6TB and a SHRINK SPACE attempt on the parent table reclaimed almost nothing for the LOB.
733 words, about 4 min4Plan Regression After a Histogram Appears
An order-entry query uses bind variables and normally returns in 40ms. After a nightly statistics gather introduced a histogram on a heavily skewed STATUS column, one customer's execution takes 8 seconds.
714 words, about 4 min5Data Guard Lag and a Truncated 300GB Table
A primary database and a physical standby use Data Guard in maximum performance mode with standby redo logs and real-time apply. RPO is 5 minutes and RTO is 30 minutes.
704 words, about 4 min6Unified Auditing Growth, Privilege Creep, and a Local TDE Wallet
The security team enables unified auditing on a 1.2TB production database. Fourteen audit policies capture every SELECT on 3,000 tables for all users.
728 words, about 4 min