ITPub博客

PARALLEL_DEGREE_POLICY Specifies whether or not automatic degree of Parallelism,statement queuing, and in-memory parallel execution will be enabled. MANUAL is the default, which disables automatic degree of parallelism, statement queuing, and in-memory parallel execution. AUTO enables automati...

Cardinality FeedbackThis blog is an extraction of https://blogs.oracle.com/optimizer/entry/cardinality_feedbackIntroduced in 11gR2. The purpose of this feature is to automatically improve plans for queries that are executed repeatedly.During the first execution of a SQL statement, an executi...

Consider the follow query against SH schema.select /*MY5*/ cust_id, sum(amount_sold) from sales where prod_id=:prod_id group by cust_id;With DBMS_XPLAN.Display_cursor, user is able to retrieve and see execution plan.SELECT t.*FROM v$sql s, table(DBMS_XPLAN.DISPLAY_CURSOR(s.sql_id, s.child_...

SQL Projection is the collective name for the columns that are Selected and returned from a query. In other words, the columns goes behind select in a query. In Oracle, a whole row is first fetched, then data values from the columns within that row are extracted into the known projection.To see th...

Sort join is the first operation of the “SortMerge Join”. Before Oracle joins two row sources, one of the row sources has tobe sorted, which is “sort join”. The name is a bit misleading. All it does is asort on the join key. The “Sort Merge Join” consists of twosteps:...

Starting with 10g, Oracle introduced “HashGroup By” as the default grouping by mechanism. Oracle employs a hash algorithm tocalculate the hash value for each row based on the GROUP BY columns. Thisallows rows with identical column values (and hence identical hash values) tobe "br...

Log levels:1. Displays the start and end of each session2. Displays level 1 and the start and end of each step3. Displays level 2 and each task executed4. Displays the SQL queries executed, as well as level 45. A complete trace, often requested during a support call 

File to Oracle databasehttp://www.oracle.com/webfolder/technetwork/tutorials/obe/fmw/odi/odi_11g/odi_project_flatfile-to-table/odi_project_flatfile-to-table.htmFile to Filehttp://www.oracle.com/webfolder/technetwork/tutorials/obe/fmw/odi/odi_11g/odi_project_ff-to-ff/odi_project_flatfile-to-flatfi...

When you open a window, let's say work repository editing, a small window pops up, and stuck at "Initializing Search Engine", it goes on and one.  You cannot wait any longer, you have to kill ODI with windows process manager. Remedy: Open ODI studio, View --> "Find ODI Object". And try to op...

Procedure signature:DBMS_STATS.GATHER_TABLE_STATS (ownname VARCHAR2,   --Owner/schema nametabname VARCHAR2,   --Table Namepartname VARCHAR2 DEFAULT NULL, estimate_percent NUMBER DEFAULT to_estimate_percent_type block_sample BOOLEAN DEFAULT FALSE,method_opt...

-Xms and -XmxThe flag Xmx is maximum memory allocation pool, while Xms is the initial memory allocation pool.XX:PermSize:The permanent space is where are stored the class, methods, internalize...

This blog is based on:http://tech.e2sn.com/oracle/troubleshooting/hang/how-to-log-on-even-when-sysdba-can-t-do-so sqlplus -prelim "/as sysdba" When archiver is stuck, users with DBA ...

du -a  | sort -nr | head -10   -a : all files, not just directory. -n: sort by string numeric value.-r:  reverse the order. By default, sort is in the ascending o...

$DOMAIN_HOME/config/config.xml, you're able to change:1. Information of security store.  

ln -s source target

This blog covers installing ODI 11.1.1.7 as well as Weblogic 10.3.6.Prerequisite:1. Oracle database 11gR2 installed.2. sysdba privilege of Oracle database 11gR2.3. Check OD...

Oracle Linux 6 U3 comes with Open-JDK 1.6 and 1.7, 1.7 is the default jvm.java -versionjava version "1.7.0_45"OpenJDK Runtime Environment (rhel-2.4.3.2.0.1.el6_4-x86_64 u45-b15...

Unable to find sources for current Linux Kernel. Specify KERN_DIR=<directory> and run againyum install gcc yum install kernel-uek-devel-$(uname -r)

SQL> show relrelease 1102000300SQL> select dept.deptno, emp.enamefrom dept left outer join emp on dept.deptno=emp.deptnoorder by deptno nulls last;    DEPTNO ENAME-------...

Viewing extract/replicat's read/write position and whether it's in recovery - must be in running:send xxx statusWhether or not extract/replicat has processed all the records from the sourcesen...