Lateral views and filter predicate pushdown
That is another optimizer issue I came across this week while working with developers on tuning application queries.
Oracle¶
srvctl config database OSDBA and OSOPER groups not defined
I have recently investigated why there are some databases in my environment which are shown with empty OSDBA or OSOPER groups.
A case for DATAFILECOPY FORMAT
I was migrating several databases from AWS EC2 non-Nitro based instances to Nitro-based ones when I came across one issue with Oracle Recovery Manager (RMAN). This blog post is about it.
ORA-01031 select V$RESTORE_POINT in PL/SQL
This blog post is about an issue with V$RESTORE_POINT and ORA-01031 that I encountered after upgrading one database to 12.2.
OEM Target Version not updated after applying RU patch
After applying the 12.2.0.1.190416 Release Update (RU) patch, I noticed that the target version had not been updated.
Concatenation and filter subqueries oddity
While investigating a poor query performance issue, I came across the following Real-Time SQL Monitoring report from a 12.1 database.
PL/SQL Create or Replace Optimization
Oracle said in their Student Guide for 12c that a local user cannot utilize system privileges on a common user's schema. When I initially checked that preposition, I was a little bit puzzled by the behavior discussed in this post.
Bitmap Conversion to ROWIDs with Global Indexes
While working with developers on optimizing a query, I discovered a limitation of the BITMAP AND operation.
Index full scan min/max scans returning wrong results on partitioned tables
A developer has recently shown me an interesting wrong results issue in one of our 12.1.0.2 databases. Having investigated it, I identified the root cause of that issue and constructed a simple test case that can be used to reproduce it.
Asynchronous Global Index Maintenance and Recycle Bin
Got an Oracle error ORA-38301: "can not perform DDL/DML over objects in Recycle Bin" in the alert log.