ORATraining Blog

Many of you would have noticed that while launching forms from Oracle Applications 11.5.10 using Internet Explorer (IE 7) then it might crash with following error. Though it may work perfectly fine in mozilla firefox.

This is the working fix for the issue.

Solution-1:

1) Take backup of jvm.dll located at c:\Program Files\Oracle\JInitiator 1.3.1.21\bin\hotspot directory.
2) Copy jvm.dll from C:\Program Files\Java\jre1.6.0_07\bin\client (or whichever highest version of jre you have) to c:\Program Files\Oracle\JInitiator 1.3.1.21\bin\hotspot
3) Clear browser cache and also Oracle Jar cache (Remove all files from c:\documents and settings\<username>\Oralce Jar cache)
4) Close all the browsers and restart

Enjoy !! The issue should have been resolved now !

Solution-2:

In case if you are unable to find the jvm.dll in that location or if the above solution didn’t work for you, you can download the working jvm.dll from this link.

Oracle PL/SQL Quick Reference

 
PL/SQL Block Structure

DECLARE --Optional

  --Variables, Cursors, User-defined exceptions

BEGIN --Mandatory

  --SQL statements

  --PL/SQL statements

EXCEPTION --Optional

  --Actions to perform when errors occur

END; --Mandatory

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Oracle SQL Quick Reference

SELECT Query Statement

SELECT [DISTINCT] {*, column [alias],…}

FROM table

WHERE condition(s)]

ORDER BY {column, exp, alias} [ASC|DESC]]

NOTE:

Avoid using DISTINCT with large table as it first does sorting of all the rows and then eliminates duplicate rows, so need a full table scan and thus it’s very slow.

ORDER BY is the last clause to get executed and thus could see all the column aliases; You can sort by a columns that is not in SELECT list; Default sorting order is Ascending (ASC)

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Oracle SQL Tuning Tips

consideration when writing an SQL statement is that it returns a correct result. The second is that it be the most efficient for a given situation.  You can use many different SQL statements to achieve the same result. It is often the case that only one statement will be the most efficient choice in a given situation.

Remember that processing SQL is a sequence of Parse (syntax check and object resolution), Execution (required reads and writes), and Fetch (row results retrieved, listed, sorted, and returned). SQL “tuning” consists, quite simply, of reducing one or more of them.

Note: generally Parse is the greatest time and resource hog. Parse overhead can be minimized by the use of Procedures, Functions, Packages, Views, etc.

Inadequate performance can have a significant cost impact on your business. A poor performing system and application can result in customer dissatisfaction, reduced productivity, and high costs. It is absolutely critical that the system’s performance is operating at its peak levels.

Following are some general tips that often increase SQL statement efficiency. Being general they may not apply to a particular scenario. Read more…

Using SQL*Plus

SQL*Plus is a command-line tool that provides access to the Oracle RDBMS.

SQL*Plus enables you to:

• Enter SQL*Plus commands to configure the SQL*Plus environment
• Startup and shutdown an Oracle database
• Connect to an Oracle database
• Enter and execute SQL commands and PL/SQL blocks
• Format and print query results

SQL*Plus is available on several platforms. In addition, it has a web-based user

interface, iSQL*Plus.

SQL*Plus is a client terminal software allowing users to interact with Oracle server to manipulate data and data structures. Users type in SQL statements in SQL*Plus that send statements to Oracle server. Oracle server then validates and executes the statements on its databases. The query results are returned to SQL*Plus and displayed to the user.  Besides sending SQL statements to the server, SQL*Plus also saves them into a local buffer and allow users to view and change the statements. The following figure illustrates the process. Read more…