Submitted by sreedevi_83 on Fri, 2009-07-31 00:38
Database tables are structured in columns and rows. However, some data lends itself to switching row data as column data for expository purposes. The pivot operation in SQL allows the developer to arrange row data as column fields. For example, if there are two customers who have both visited a store exactly four times, and you want to compare the amount of money spent by each customer on each visit, you can implement the pivot operation.
Submitted by gavsal on Fri, 2009-07-17 02:40
Checks to be performed at the machine level (note the example is Red Hat Linux)
run queue should be ideally not more than the number of CPU’s on the machine
At the maximum it should never be more than twice the number of CPU’s.
This is denoted by the column ‘r’ in the vmstat output shown below
vmstat – 5
procs memory swap io system cpu
r b swpd free buff cache si so bi bo in cs us sy id wa
4 1 488700 245704 178276 12513572 0 1 10 17 48 1365 40 12 43 5
Submitted by dafon on Thu, 2009-04-30 10:13
When importing table that contained custom type, you will encounter an oracle error as shown below:
Import of table containing object type(s) fails with IMP-00061 IMP-00063
Submitted by knight on Thu, 2009-04-02 00:29
RMAN is recommended for backups/restore of oracle databases.It is a very powerful tool and has variety of useful features.There is 'checksyntax' feature in RMAN which allows one to check RMAN scripts syntactically without executing it.This feature is available from 10G release 2.It proves to be useful for checking scriptsfor live databases where one doesnt have leisure to execute scripts any time and any times!!
bash-3.00$ vi rman_bkp.rman
Submitted by rnanton on Tue, 2009-03-10 19:10
Here’s an alternative to the union statement for creating a collection of values using the Oracle SQL Model construct in 10g.
Submitted by bhavin_rudani on Wed, 2009-02-04 07:20
Even though readability doesn't affect the actual performance of SQL statements, good programming practice calls for readable code. Readability is especially important if you have multiple conditions in the WHERE clause. Anyone reading the clause should be able to determine whether the tables are being joined properly and should be able to understand the order of the conditions.
Try to read this statement:
Submitted by admin on Sun, 2009-01-11 23:33
According to the Enterprise System Spectator's website Oracle is busy laying off a large number of employees. According to the article, 8000 people or 10-15% of the company's workforce will lose their jobs today. Apparently similar layoffs are happening at SAP, Infor and possibly several other companies.
Submitted by tlananthu on Thu, 2009-01-08 08:32
Answer: Although this may be a undervalued question, I got many a search for my blog with this question. This is where I wanted to address this question elaborately or rather in multiple ways.
Submitted by pete91z on Fri, 2009-01-02 07:50
I've been working on way to capture changed rows using ora_rowscn for part of an ETL routine. Here are some details of what I've tested and found.
By default, the ora_rowscn pseudo column reports the scn at block level. This means that rows sharing the same block will have the same ora_rowscn, and if one row were to be changed, then scn would be altered for both blocks.