Oracle DBACategory

1.Let me  create a test case : I will take different OS statistics and run time statistics to compare with AWR report generated after execution. Case A.About test case in lower CPU:- I will create a table first create table t (id number, sometext varchar2(50),my_date date) tablespace data; Now I… Continue Reading AWR report analysis in 12c depth-part 1

Adaptive Cursor Sharing:   This document will explain step by step to analyze adaptive cursor sharing. Let’s start with the basics. Let’s create a table as a copy of dba_objects.   SQL> create table t as select * from dba_objects; Now, if we run a query like ‘select object_name from… Continue Reading Adaptive Cursor Sharing

First we need to load data SQL> alter session set tracefile_identifier=’ABC’; Session altered. Elapsed: 00:00:00.01 SQL> alter system set events ‘10046 trace name context forever, level 12′; System altered. Elapsed: 00:00:00.18 SQL> create table t1(c1 number,c2 char(2000)); Table created. Elapsed: 00:00:00.03 SQL> set autotrace on; SQL> set autotrace traceonly; SQL>… Continue Reading Comparison between exadata and non-exadata executions test case

Logical IO vs Physical IO vs Consistent gets I have created 1 GB table T1.   Let me check how many blocks are there in the table after I have analyzed it.   SQL> select BLOCKS from user_tables where table_name=’T1′;    BLOCKS ———-    139153   Autotrace report Let me clean buffer… Continue Reading Logical IO vs Physical IO vs Consistent gets oracle

I referred some reference from my favorite Tim Hall blog (ORACLE_BASE) A.Basic of optimizer statistics: – The optimizer cost model relies on statistics collected about the objects involved in a query, and the database and host where the query runs. Statistics are critical to the optimizer’s ability to pick the… Continue Reading Oracle 12c gather statistics oracle deep dive

OMS Server: Where runs the Enterprise Manager Middleware Client Server: Where we’re going to install the agent 1.Pre-requisites setup to be done in Client Server Create directory where agent will be installed in Client Server In Client,You need to create a directory or mount point as /u01/oemcc Install telnet in… Continue Reading Oracle 13c cloud control agent installation

What is PGA The Program Global Area (PGA) is a private memory region that contains the data and control information for a server process. Only a server process can access the PGA. Oracle Database reads and writes information in the PGA on behalf of the server process. An example of… Continue Reading Oracle PGA (Program Global Area) in 12c