Reserved words in Oracle databases
In Oracle databases, many words are reserved for specific uses or entirely. This helps eliminate typos in SQL statements. You...
March 18, 2026
2026
Index quality in Oracle databases
Index quality is a factor that directly affects the overall database performance. The quality of an index is measured by...
March 18, 2026
Setting threshold values for metrics on Exadata database servers using DBMCLI
Exadata database servers also allow setting threshold values for metrics, similar to cell nodes, and sending notifications when these thresholds...
March 18, 2026
Identifying the serial numbers of Exadata and its components
You can use the following commands to identify the serial numbers of Exadata and its components. Exadata Rack It can...
March 18, 2026
How to find which objects are causing enq: HW – contention wait event ?
Enqueues are shared memory structures (locks) that serialize access to database resources. They can be associated with a session or...
March 18, 2026
How to convert LOB data stored as basicfile to securefile ?
SecureFiles LOB storage is one of two storage types used with Oracle databases; the other is BasicFiles LOB storage. Several...
March 18, 2026
How to find when a table was last modified
For each row in a table, ORA_ROWSCN returns the SCN information of the last change made to that row. This...
March 13, 2026
Enabling debugging in RMAN
Debugging/monitoring can be performed to obtain more detailed information about RMAN processes. This allows us to gain more insight than...
March 13, 2026
ORA-12988: cannot drop column from table owned by SYS
When attempting to delete a column from a table owned by a SYS user, the error “ORA-12988: cannot drop column...
March 13, 2026
Read Only Table Partitions
Read-Only Partitions Starting with Oracle version 12.2, partitions or sub-partitions of a table can be marked as read-only. This can...
March 13, 2026
Assertions Use Cases in Oracle
Assertions are boolean expressions that have the semantics of a constraint. The database must ensure the truth of these boolean...
March 12, 2026
Free Gateway to Oracle Database (Free SQL)
For developers, students, and database enthusiasts, getting hands-on practice with a powerful database system like Oracle has often required...
March 5, 2026
PDB Lockdown Profiles
PDB Lockdown Profiles are a security feature in Oracle’s multitenant architecture that allows administrators to restrict specific operations and features...
March 5, 2026
Oracle Flex Clusters
Oracle Flex Clusters From Oracle Grid Infrastructure 12c Release 2 (12.2) onward, all cluster configurations are implemented as Oracle Flex...
March 3, 2026
Transparent Application Continuity (TAC)
What is Transparent Application Continuity (TAC)? With the release of Oracle Database 18c, Transparent Application Continuity introduces an automated method...
February 27, 2026
