In the previous blog, I demonstrated creating an empty table with BASIC Compression and then populating it.
To quote the 11.2 documentation, “Although it is referred to as block compression, it might be helpful to think of block compression as block skipping“.
Unlike tracing for particular SQL statements, you can also trace by PID (Oracle PID) or Server Process ID (SPID).
My previous blogpost covered using ALTER SYSTEM/SESSION to set tracing for a specific SQL_ID that has been determined in advance.
So far, the previous examples have been on tracing the Execution of SQL statements and/or the Execution Plan used.
In the previous posts, I have traced eitherSELECTorINSERT or UPDATE or DELETEstatements I have pointed out that the block statistics are reported as “FETCH” statistics for SELECTs and “EXECUTE” statistics for the DMLs What if we have an INSERT … AS SELECT ?
So far, all the examples of SQL Tracing that I have provided in this series are for SELECT statements.