What is SQLcl ?
SQLcl is a new command line interface like SQL*PLUS coming along with SQL Developper 4.1 Early Adopter. It is a lightweight tool (only 11MB) developed by the SQL Developer team fully compatible with Windows and Unix/Linux. You don’t need to install it so it is totally portable.
The tool does not need any Oracle client to be installed, however you need a JRE 7.0 or newer.
Continue reading SQLcl, a revolution for SQL*Plus users
This query returns the top 5 wait events for the last hour from the v$active_session_history view.
Be careful, this view is part of the diagnostic pack, you should not query this view if you not licensed for it.
Top 5 wait events from v$active_session_history
select * from (
count(sample_time) as EST_SECS_IN_WAIT
where sample_time between sysdate - interval '1' hour and sysdate
group by WAIT_CLASS,EVENT
order by count(sample_time) desc
where rownum <6
This is obviously an approximation, because v$active_session_history contains only 1 second samples, and who knows what happens during each second sample. If you compare the time given by this query with information from v$system_event it will not exactly match but you should be close if you choose a sufficiently long period.
What is Oracle Data Redaction ?
- Oracle Data Redaction is meant to mask (redact) sensitive data returned from application queries.
- Oracle Data Redaction doesn’t make change to data on disk, the sensitive data is redacted on the fly before it is returned to the application.
- You can redact column data by using one of the following methods:
- Full redaction. You redact all of the contents of the column data.
- Partial redaction. You redact a portion of the column data.
- Regular expressions. You can use regular expressions to look for patterns of data to redact.
- Random redaction. The redacted data presented to the querying application user appears as randomly generated values each time it is displayed, depending on the data type of the column.
- No redaction. The None redaction type option enables you to test the internal operation of your redaction policies, with no effect on the results of queries against tables with policies defined on them.
Continue reading OCP 12C – Oracle Data Redaction