Find Query Versions

SQL to find Query Versions based on a particular SQL_ID
=> you can remove the columns selected based upon your need.

Select inst_id, sql_id,address, hash_value, sql_text, version_count,loaded_versions,
executions,loads,invalidations
from gv$sqlarea
where version_count >= 1
and sql_id ='&Input_SQL_ID'
order by inst_id,version_count
/

Find historical data using SQL_ID

SET LINESIZE 120
SET PAGESIZE 1000
col snap_begin format a35
COL executions FOR 999,999,999
COL elapsed_time FOR 999,999,999,999
COL avg_ms FOR 9999999.99
COL min_ms FOR 9999999.99
COL max_ms FOR 9999999.99
SELECT
TO_CHAR(TRUNC(snapshot.begin_interval_time,'HH24'),'DD-MON-YYYY HH24:MI:SS') || ' EDT' SNAP_BEGIN,
sqlstat.instance_number,
SUM(sqlstat.executions_delta) executions,
MIN(sqlstat.elapsed_time_delta / sqlstat.executions_delta / 1000) min_ms,
MAX(sqlstat.elapsed_time_delta / sqlstat.executions_delta / 1000) max_ms,
SUM(sqlstat.elapsed_time_delta) / SUM(sqlstat.executions_delta) / 1000 avg_Ms
FROM
dba_hist_sqlstat sqlstat,
dba_hist_snapshot snapshot
WHERE
sqlstat.dbid = snapshot.dbid
AND sqlstat.instance_number = snapshot.instance_number
AND sqlstat.snap_id = snapshot.snap_id
AND sqlstat.sql_id = '&1'
AND snapshot.begin_interval_time >= SYSDATE-60
GROUP
BY TO_CHAR(TRUNC(snapshot.begin_interval_time,'HH24'),'DD-MON-YYYY HH24:MI:SS') || ' EDT',
sqlstat.instance_number
ORDER
BY snap_begin
/

SAMPLE OUTPUT

Enter value for 1: 6ajkhumm78nrp

SNAP_BEGIN                          INSTANCE_NUMBER   EXECUTIONS      MIN_MS      MAX_MS      AVG_MS
----------------------------------- --------------- ------------ ----------- ----------- -----------
01-JUL-2015 00:00:00 EDT                          1            2    16160.94    16569.28    16365.11
01-JUL-2015 00:00:00 EDT                          4            2    16530.52    96809.78    56670.15
01-JUL-2015 01:00:00 EDT                          1            2    16008.20    16273.29    16140.74
01-JUL-2015 01:00:00 EDT                          4            2    96150.86    96213.51    96182.18
01-JUL-2015 02:00:00 EDT                          1            2    16417.98    16606.18    16512.08
01-JUL-2015 02:00:00 EDT                          4            2    96991.15    97816.36    97403.75
01-JUL-2015 02:00:00 EDT                          5            2   121063.36   271762.59   196412.97

Troubleshooting 'log file sync'

Very Good Document on "log file sync" on My Oracle Support Site.
Troubleshooting: 'Log file sync' Waits (Doc ID 1376916.1)

http://www.pythian.com/blog/adaptive-log-file-sync-oracle-please-dont-do-that-again/

Oracle GoldenGate Limitations and Restrictions

Oracle GoldenGate supports two types of capture:

Classic Capture
Integrated Capture

Classic Capture
Oracle GoldenGate continues to support the existing Capture module, now referred to as Classic
Capture, which directly accesses the database redo logs looking for DML changes to capture for
distribution.
It is possible to capture from redo logs stored inside of ASM. Adjusting the read
size can improve Extract performance. In this mode, Extract can be integrated
with Oracle RMAN to manage log retention.


Excellent Post by another DBA - Credit goes to him.
http://sandeepnandhadba.blogspot.com/2014/12/oracle-golden-gate-12-bidirectional.html