Synonyms in PL/SQL

Hi falks,

In pl/sql synonym refers to schema objects which are created by a particular user to access an objects which  didn't belongs to him.Sometimes we have to join certain modules of a product to retrieve data for business purposes. Normally the particular user has to create the synonym for the related object according to the data requirement. The owner of the object should give grants for this user. 

Owner can create synonyms and give grants to other users who are using different schema s.

User cannot create a synonym for different schema other than his own schema from different schema other than his own schema.

Example statement of creating synonym from different schema for a certain table. Just imagine that your schema is ABC and other schema which include the table you want is DEF and table is employees. Statement is,

      CREATE OR REPLACE PUBLIC SYNONYM synemployees FOR ABC.employees;

User don't have to give any kind of grants to the synonym for his schema. It will assign all the grants automatically when synonym is creates.
But user can give grants to other users (schemas) while creating the synonym.

Anagram words in text file and file write and replace text through java

Hi all,

Before few days I was having an assignment which need to apply Anagram to the words in a given text file through java. No way of using predefined methods or algorithms for this. Therefore I created simple java program to do this. This might also help you to understand about anagram and some techniques of applying anagram through java.

This is the source code.....

Just imagine that the existing file name is "test"

import java.io.*;
import java.util.StringTokenizer;
 
public class FileRead {

    static String sentence [];
    static String temp [];
    static int i = 0;
    static String first="";

 public static void Read() {

  try{

  // Read the existing text file

  FileInputStream fstream = new FileInputStream("test.txt");
  DataInputStream in = new DataInputStream(fstream);
  BufferedReader br = new BufferedReader(new InputStreamReader(in));
  
  String strLine;
 
  while ((strLine = br.readLine()) != null) {

     StringTokenizer stk = new StringTokenizer(strLine);
     sentence = new String[stk.countTokens()];
    temp = new String[sentence.length];
    while(stk.hasMoreTokens()) {
    sentence[i] = stk.nextToken();
    i++;

  }
  for(int x=0;x<sentence.length;x++){

if(x==0){
temp[x]= sentence[(sentence.length-1)];
}
else{
temp[x]= sentence[x-1];

}

  }
  for(int x=0;x<temp.length;x++){
     first=first+temp[x]+" ";

  }
  // Print original sentence
  System.out.println (strLine);
  System.out.println ("\n");
  System.out.println ("Apply anagram for the above sentence.");
  //Print Anagramed sentence.
  System.out.print (first+"\n");

  first="";

You can write this new phrase by using Filewritter and Bufferwritter as below mentioned. I'm using new text file to write new phrase......

// Write Anagramed sentence to new text file
File file =new File("test1.txt");
    //if file doesnt exists, then create it
    if(!file.exists()){
    file.createNewFile();
    }
    FileWriter fileWritter = new FileWriter(file.getName(),false);
    BufferedWriter bufferWritter = new BufferedWriter(fileWritter);
    bufferWritter.write(first);

The statement "FileWriter fileWritter = new FileWriter(file.getName(),false);" includes "false" in the end of the statement. We can use true instead of using false. The different of these two is , we can write new word or phrase right after the existing word or phrase in the text file by using "true". When we use "false" it will replace the existing word or phrase by given word or phrase.

How to put existing tab canvas on a newly created content canvas

Hi fellas,

                               Before few days i got a oracle form which has a tab canvas to display the items of the form. One particular tab include 2 buttons which have to be common to all three tabs. At that time it only belongs to the first tab of the canvas. Part of my task is to make those to buttons common to all three tabs. Given solution is for this is create a new content canvas and place existing tab canvas on that content and place above mentioned two buttons on the content canvas. Content canvas should be larger than the tab canvas. Other wise those button wont get display on the form.
                               If you have to create both the content canvas and tab canvas you can simply create a content canvas and can draw a tab canvas on that content canvas. No need to have set any property or anything else for that. But when you have a existing tab canvas, you just cannot create new content canvas and place or set the tab canvas on that. In a situation like this we can use different method to do this.
                               First create a content canvas and make it larger than the existing tab canvas. Then double click on the new content canvas and click on the VIEW tab of the form builder and select STACKED VIEWS.. After that you will get a window which is showing the existing canvases.

                         In that window you can select the canvas you need to set on the newly created canvas. Now Our tab canvas is displaying on the content canvas and simply we can place the above mentioned two buttons on the content canvas. Now those two buttons are common to all three tabs. We don't have to set any kind of property for this.

How to extract only number values from given string....

Hi fellas,

                         In oracle development, sometime we have to extract only the numbers from the given string. If the given string is has a dynamic length we can use TRIM for this task. But we have select whether it is LTRIM or RTRIM. Just imagine we have a string like '-4646'. We have to extract the numbers without '-'. We can use below statement for that.
                               select LTRIM('-4646','-') from dual;
If the unwanted part of the string ('-' in the example) is in left side, we can use LTRIM. If it's on the right side, we can use RTRIM.
Just imagine we have a string like '---00045454' and we have to extract only '45454' from the string. Also the length of this string can be change. Its dynamic. Apart from that the number of numbers in the string can be change and the number of '-' s and '0' can be change. In this kind of a situation we can use TRIM like below.
                              select LTRIM ( LTRIM (  '---00045454' , '-' ) , '0' ) from dual;

You can use both LTRIM and RTRIM like below for some situations.
                             select RTRIM ( LTRIM ( '----4587000' , '-' ) , '0' ) from dual;

You can use number of times of trims in your statement accordingly. The major thing you should consider is that you should give the characters you want to delete in a proper order. Otherwise it wont give the real output you want. The other thing you should consider about is select the trim you should use according to the places of the characters (RTRIM or LTRIM).   

You can use trim within trim in your statements. In those kind of situations,the most inner trim will trim the value accordingly and pass the resulted value to the previous trim. This trim will trim the value accordingly and pass the value to his previous trim and so on and on. You can use this function with REG_EXP_REPLACE simultaneously.
TRIM function is really suitable for the situations like 

• String has a dynamic length.
• Number of  unwanted characters can be change by time to time.
• Both starting point and ending point includes unwanted characters.

Trim couldn't filter all the characters. But he will do somethings for you when he fit to the situation.

How to put a hyperlink in Oracle forms.....

Hi fellas,
                  Hyperlink is something like a URL. we can click on that and it will navigate us to the relevant location where we can have information we need. First of all we need to have relevant window and canvas to display the relevant information for the users. Our hyperlink will navigate the user to this newly created canvas to show the information. You can add any item like text items, display items, tables and etc...
                  To add new hyper link, first you have to add new Text item on the canvas that you need to display the hyperlink to the user. It's better change it's Visual Attribute Group as "VA_CLICK". You don't have to write anything in the "Prompt" section to display. Because hyperlinks didn't display anything in Prompt section.  Apart from that you should set BEVEL = NONE in the property palate of the text item. You should call to the newly created canvas in  WHEN-MOUSE-CLICK trigger by using SHOW_VIEW. Apart from that we can use web.Show_Document to show the relevant page to the user. But we can use web.Show_Document from within a form which run from the web.
                 If you run the form with above modification, still you wont be able to see the hyperlink. But it's there where you placed it and you can see it's functionality by clicking on the area you placed it. To display the hyperlink, you should assign a relevant name for the item within the trigger or program unit where you populate the data to the canvas where you placed your hyperlink. Otherwise it wont get display. eg - :BLK_MAIN.HYPERLINK := Hyper Link(Hyperlink name). Then only you can view this through your form.

How to compare two columns in a same table in a select statement and show a particular result ...

Hi Oracle fellas,

                        Some times in oracle developments, we have to compare various kinds of values, table columns and etc.. to give a comfortable out put for the users. In this process, some times we have to give them feedback by showing them some kind of status or a value putting to newly created column which is not in the related database table.
                        As an example, just imagine we have table name "Employees" and it include Emp_No, Emp_name, Previous_Year_Salary and Current_Year_Salary columns. We have to compare the previous salary with current salary and return a value as M if those two values are equal and NM if not equal. Apart from that we have to display above value in a separate column name "any name" which not include in Employees table. Just image that we are advised to not to add any new column to the related table.
All you have to do is write a simple SELECT statement and put two columns into decode function with two values you have to return accordingly. It's like,
SELECT  Emp_No, Emp_name, DECODE(Previous_Year_Salary , Current_Year_Salary, 'M', 'NM') 
FROM Employees;
Above statement will return all the fetched records with the relevant comparison and relevant newly added column values. You can put a name to new column like bellow.

SELECT  Emp_No, Emp_name, DECODE(Previous_Year_Salary , Current_Year_Salary, 'M', 'NM')  as 'any name'
FROM Employees;

Apart from this DECODE function includes lots of formulas we can use. Within DECODE function we can not only compare numbers, but also dates and characters as well.

ORA- 12154: TNS:could not resolve service name in Oracle Formbuilder or Report builder

Hi Oracle fellas,

                            You will get above problem when you are using oracle form builder or report builder. This can happen because of various kinds of reasons. It can happen because of the error of the TNS name you are trying to connect. May be the port numbers can be wrong or something like that. You cannot connect through form builder means that form builder cannot see or find your TNSNAMES.ora file. Form builder uses the TNSNAMES.ora file and SQLNET.ora file found under the iDS suite folder - under this folder the NETWORK - ADMIN folder. Sometimes there can be syntax errors like unrelated parentheses in your TNS name. Including these kind of error makes TNS file unusable.

To overcome this problem always maintain your TNSNAMES.ora file without any errors. Keep your .ora files in proper directory.

If you are using directory naming, 
Verify that "LDAP" is listed as one of the values of the NAMES.DIRECTORY_PATH parameter in the oracle net profile(SQLNET.ora).
Verify that the LDAP directory server is up and that it is accessible.
Verify that the net service name or database name used  as the connect identifier is configured in the directory.
Verify that the default context being used is correct by specifying a fully qualified net service name or a full LDAP Dn as the connect identifier.

If you are using easy connect naming,
Verify that "EZconnect" is listed as one of the values of the NAMES.DIRECTORY_PATH parameter in the oracle net profile(SQLNET.ora).
Make sure the host,port and service name specified are correct.
Try enclosing the connect identifier in quote marks.

Sometimes this happen when your are using particular oracle version in the first time. Reason for this kind of scenario is the problem with SQLNET.ora file. You can see few lines of statements in that .ora file. In the very first moment only first two lines were commented. Therefore you wont be able to connect to needed database via form builder or report builder. Only you have to do is comment all the lines in that file and try to connect to the database you want.

There may be different oracle products installed in your computer. Each of these products contains it's own NETWORK/ADMIN directory which is the location of .ora files. Therefore we can maintain only one TNSNAMES file for all the products in your computer. TNS_ADMIN environmental variable will allow you to do that. Take any of the TNSNAMES.ora file and put it in to a directory (like "D:\0_library") which is easily accessible and let the TNS_ADMIN environment variable point to its directory. Then do as follows,

c:\ temp>set tns_admin 
tns_admin = D:\0_library
c:\ temp

Simply log in to your database.....:)

Raise form_trigger_failure... ORACLE...

Hi Oracle fellows...:)


We all are familiar with the above phrase "Raise Form_Trigger_Failure". This statement is use  freeze the program whenever we need. Freeze means stop the whole process of the oracle program. 
Normally in Oracle forms we use this statement to freeze the form whenever an error occurred. This statement mostly helpful when you are doing higher level validations like QC validations. We can use this statement when we handle an error like prompt appropriate error message. Otherwise program will prompt an appropriate error message and will try to continue the rest of the process according to the program process and code. This will make program to prompt an Oracle error messages for user and he or she will not be able to understand those messages and will get messed up with the program.


Sometimes this statement wont work properly in WHEN_BUTTON_PRESSED trigger. Sometimes this button wont be able to freeze the form and therefore program will try to proceed with the error and will prompt an oracle error. 


This happens sometime when you are using exception handling without proper manner. I mean when trying to prompt out the exception and do nothing to handle it. Actually "Raise Form_Trigger_Failure" is an predefined exception. So in a situation like that, the program will throw you an exception without freezing it.  


For these kind of scenario, we can use above statement as below mentioned.


when form_trigger_failure
Raise Form_Trigger_Failure;


Pretty easy stuff. But you have to put these two lines within the exception handling part. It will work in a nice and smooth manner...

FRM-40735:ON-ERROR trigger raised unhandled exception ORA-06508

After converting older version of oracle forms to forms 10g using forms Migration Assistant, you are not be able to open the application or log in to the application via web. When access from developer suit 10g, it will run without any problems. One of the problem could be the related ORACLE LIBRARY PATH which attached to it. Some times this can happens when you are changing the library path according to the module or work area you work at that moment.


In older versions of forms the library path is mapped to the client pc and the forms application refer to the mapped drive letter. In the web we couldn't find specific path. It is relative. It will automatically refer the path.


If you have above mentioned problem, you will get message from oracle form builder. It says cannot attache specific libraries to your form source. Sometimes you wont get this message but wont be able to open the form. when you look in to the form source in form builder, you will see that form didn't include any library. 


There's few solution available for this matter. 

• Open the form in Oracle form builder. Click on Attached library and plus sign item on Object Navigator.  Locate the need .plls and press YES on the message which ask whether to remove path or not.
• Go to the regedit through Command Prompt. Go to forms_path if you are  working with 10g2 , otherwise go to forms90_path and enter the related library path to that.
• Go to the Oracle folder where installed it in your computer and go to the forms folder if you are using oracle 10g2. Otherwise go to forms90 folder. In that folder, go in to the server folder and you can find ENV file named Default. open it on notepad or wordpad. It includes something like "FORMS_PATH" if you are using 10g2. Otherwise "FORMS90_PATH" give the related library to that path and save it. Now whole forms is under your control. 

Now you can open the form and access via web successfully. 


Additional....

• Don't use long paths for Library folder.
• Keep the latest libraries which are in SVN.
• Always replace the regedit path and default.env path when you are changing the module or oracle version accordingly.
• Oracle 10g1 use FORMS90 AND Oracle 10g2 use FORMS.