Trace Files -- 9 : Advantages
I received a question about why Trace Files are useful.I jotted down a few quick points. I may expand on them or add to them laterYou don’t have to monitor a user screen , batch job in real time –...
View ArticleTrace Files -- 10 : Tracing DML
So far, all the examples of SQL Tracing that I have provided in this series are for SELECT statements. (By "DML" I mean INSERT / UPDATE / DELETE statements other than SELECT statements)Examples of the...
View ArticleTrace Files -- 10b : More DML Tracing
In the previous post, I demonstrated what a trace of UPDATE or DELETE would show (or not show). For example, although Index blocks need to be updated, we cannot identify how many Index blocks were...
View ArticleOracle High Availability Demonstrations
A link to Oracle High Availability Demonstrations....
View ArticleTrace Files -- 10c : Query and DML (INSERT)
In the previous posts, I have traced eitherSELECTorINSERT or UPDATE or DELETEstatementsI have pointed out that the block statistics are reported as "FETCH" statistics for SELECTs and "EXECUTE"...
View ArticleTrace Files -- 11 : Tracing the Optimization of an SQL Statement
So far, the previous examples have been on tracing the Execution of SQL statements and/or the Execution Plan used.But what if you want to trace the Optimization --- identify how the Optimizer...
View ArticleTrace Files -- 11b : Using DBMS_SQLDIAG to trace the Optimization of an SQL...
My previous blogpost covered using ALTER SYSTEM/SESSION to set tracing for a specific SQL_ID that has been determined in advance. The SQL may be executed in the future after the ALTER...
View ArticleTrace Files -- 12 : Tracing a Particular Process
Unlike tracing for particular SQL statements, you can also trace by PID (Oracle PID) or Server Process ID (SPID).SQL> select s.sid, p.pid 2 from v$session s join v$process p 3 on (s.paddr=p.addr) 4...
View ArticleRMAN : Unused Block Compression and Null Block Compression
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". 11.2 differentiates between Unused Block...
View ArticleCompression -- 1 : BASIC Table Compression
Now, starting a new series of blog posts on Compression.Beginning with BASIC Table Compression.Basic Table Compression was introduced in 9i Release 2 (9.2.0). It is free with the Enterprise Edition....
View ArticleCompression -- 1b : (more on) BASIC Table Compression
In the previous blog, I demonstrated creating an empty table with BASIC Compression and then populating it.What if you have a pre-existing table with data that you want to compress ?Here I start with a...
View ArticleRecent Blog Series on RMAN
These have been my recent blog posts on RMAN1. 1 Backup Job Details (Jun-15)2. 2. ArchiveLog Deletion Policy (Jun-15)3. 3. The DB_UNIQUE_NAME in Backups to the FRA (Jun-15)4. 4. Recovering from...
View ArticleRecent Blog Series on (SQL) Tracing
These have been my recent blog posts on (SQL) Tracing1. 1. Generating SQL Traces (own Session) (Sep-15)2. 2. Generating SQL Traces (another Session) (Sep-15)3. 3. Tracing for Specific SQLs...
View ArticleCOMPRESSION -- 2 : Compressed Table Partitions
A Partitioned Table can choose to have a mix of COMPRESS and NOCOMPRESS Partitions.As in this case where the first 3 partitions are defined as COMPRESS and the last as NOCOMPRESS : :[oracle@localhost...
View ArticleCompression -- 3 : Index (Key) Compression
Unlike Table Compression that uses deduplication of column values, Index Compression is based on the keys. Key Compression is also called Prefix Compression.This relies on repeated leading key values...
View ArticleCompression -- 4 : RMAN (BASIC) Compression
BASIC Compression in RMAN is free with the Enterprise Edition. Advanced Compression with a specified algorithm requires the Advanced Compression Option Licence. RMAN> backup as compressed backupset...
View ArticleCompression -- 5 : OLTP Compression
Taking the test case from my first Blog Post on compression, is there any way to support OLTP ?As demonstrated in the first Blog Post and here, once the table undergoes DML, its size...
View ArticleNow an OCP 12c
I have upgraded my Oracle Database Certified Professional status from 11g to 12c, having passed the 1Z0-060 Exam last Monday.This is the list of material I used :1. Documentation : Oracle 12c...
View ArticleFBDA -- 1 : Testing Flashback Data Archive in 12c (NonCDB)
Note : At the bottom of this post, you'll find links to more (subsequent) posts on this topic.Some testing I'd done with Flashback Data Archive (henceforth called FBDA in this and subsequent posts, if...
View ArticleFBDA -- 2 : FBDA Archive Table Structure
Following up on my earlier post, I look at the FBDA Archive Tables.[oracle@ora12102 Desktop]$ sqlplus hemant/hemantSQL*Plus: Release 12.1.0.2.0 Production on Sun Apr 3 23:26:27 2016Copyright (c) 1982,...
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