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Automatic Statistics Gathering does not Complete - Diagnostics Interpretation Guidelines (Doc ID 1902112.1)

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DBMS_STATS Tracing

Tracing is enabled by calling dbms_stats.set_global_prefs(‘trace’,<trace flags>)

Following are the possible values for the trace flags:

1 = use dbms_output.put_line instead of writing into trace file

2 = enable dbms_stat trace only at session level

4 = trace table stats

8 = trace index stats

16 = trace column stats

32 = trace auto stats – logs to sys.stats_target$_log

64 = trace scaling

128 = dump backtrace on error

256 = dubious stats detection

512 = auto stats job

1024 = parallel execution tracing

2048 = print query before execution

4096 = partition prune tracing

8192 = trace stat differences

16384 = trace extended column stats gathering

32768 = trace approximate NDV (number distinct values) gathering

Use a combination of flags to combine different tracing levels.

e.g.

exec dbms_stats.set_global_prefs('trace',to_char(512+128))