fbar timer – Active Session History Instrumentation Gap
Unaccounted database time in ASH caused by fbar timer wait event. Continue Reading
Author: Nenad Noveljic
Troubleshooting an emcli Login Problem
A hidden dependency in emcli Continue Reading
Tracing Library Cache Locks 3: Object Names
A fully-fledged gdb script for tracing library cache locks Continue Reading
Tracing Library Cache Locks 2: Using Debugger
Library cache lock allocations aren’t instrumented in Oracle database, but we can extract this information with debugger. Continue Reading
Performance Problem with Incremental Statistics Calculation
A frequently executed SQL causes problems with the initial incremental statistics calculation. Continue Reading
Duplicating Pluggable Databases with sysbackup
Duplicate of pluggable databases doesn’t work with SYSBACKUP. The privilege rule seems to be hardcoded in an Oracle C function. Continue Reading
Incremental Statistics: Histogram Pitfall
The creation of new histograms invalidates synopses. Continue Reading
Improved ORA-04036 Diagnostics in Oracle 19c
Top consumer information included in the incident file. Continue Reading
Wrong Join-Cardinality with Extended Statistics
Wrong cardinality calculation for multi-column join with filter predicate and extended statistics Continue Reading
ORA-07445 in qksqbCheckProp() with Inline Hint
Inline hint can cause ORA-07445 in 18c and 19c. Continue Reading