JDBC :: Resultset Data Processing - Default Fetchsize Returned
Jan 21, 2015
I have observed a strange behaviour from Resultset object. My application fetches 400 records from a table and processes these records every 10secs. By default the resultset has a fetchsize of 10 from the database cursor. As I understand if the query returns 400records, the resultset will fetch 40times, in multiple of 10 to get all these 400 records from database cursor.
Query : SELECT * FROM ( SELECT * FROM TestTable
WHERE STATE_ACTION = 0 ORDER BY ROP_TIME DESC )
WHERE ROWNUM <= 250
Observation : Under a normal operation, the resultset fetches all the 400 records on query execution from database cursor, but under unknown conditions the same resultset object fetches only 10 records from the database cursor and exits. Please refer page 297 in document below for the result fetch size details. JDBC developer guide for oracle 10g : [URL] .... This condition self-heals itself in few hours or restarting the database or restarting the server. The root cause of this behavior is unknown.
query ="Select major_career.Major_Title, career.ISCOTitle,career.FS.... " //only partial, // I swear the query is correct resultSet = statement.executeQuery(query); //this executes it relArr = new ArrayList<String>(); //don't worry it is intialized
In the code below I tried to store the resultset components into the arraylist
int j = 1; while (resultSet.next()) { while(j<=numberOfColumns){ relArr.add(resultSet.getObject(j).toString()); j++; } } // end while
I am not sure whether the arraylist is able to store the result set because when i try to display it like show below it only shows some rows and only the first column
Iterator it = relArr.iterator(); while (it.hasNext()) { System.out.println(it.next());
I want to manipulate the resultset results in my program by copying the resultset values to other datastructures.
I have retrieve the data in listbox from my database already and now again i want to select the data from this listbox and query on it , is it possible?
For Ex i have listbox as follows
<h4>Models For Selected Pattern:</h4> </br> <select Name="drop_model" multiple="true"> <%
I am very new to multithreading thus the code below reeks of ignorance,but i guess thats a place to start from.I am trying to obtain values that are already in my db and send them to a database by creating a new thread as follows:
//ADDED JUL 15 2014 12:07, LISTITEMS SO public void getList() throws SQLException { String sql = "select * from PRODUCTS"; out.print(m_Stmt); ResultSet rs = m_Stmt.executeQuery(sql); ExecutorService es=Executors.newCachedThreadPool(); es.execute(new Runnable(){ @Override
I have a requirement where we have an ETL jobs that runs in the backend which will get the up to date data from various sources , here we have both structured and unstructured data and the data capacity is massive which is in petabytes. Based on the data that is fetched we need to come up with a consolidated data view for the data which we retrieved. My queries are:-
1) How to create a consolidate data view , in what form it will be in (XML, JSON, etc)? whether we need to come up with a unified data model as the data is both structured and unstructured format? If so how we can go about it?
2) Since the data is really massive, how we can construct the consolidate data view? whether we need to create it in small chunks or whether we need to store these data in a cache or DB from where we will retrieve it and form the consolidated data view?
3) To process these data whether we need to have any Hadoop clusters to process these data parallel? As we are talking about massive data in the form of structured and un structured format?
4) Whether there is a need for NoSQL database to support unstructured data? If we are supposed to store the data?
As shown in the SS I show the data of the batch from the db.Now I want to edit the data of the jtable using the default Double editors and also show the data using a Date renderer in dd/MM/yyyy format.The problem is when the data is loaded from the db,I am not knowing how to implement and set the editors to double and date.I am new in java.The code of the above is shown as follows.
Java Code: /* * To change this template, choose Tools | Templates * and open the template in the editor. */ package Billing; import java.awt.Component; import java.sql.Connection; import java.sql.Date; import java.sql.PreparedStatement; import java.sql.ResultSet;
calling a parameterized stored procedure in java jdbc from sql server.The stored procedure goes like this in sql
create proc patientreg @id int as begin select [patient_id],[Psurname], [pFirstname], [pMiddlename], [reg_date], [DOB], [Sex], [Phone_num], [Addr],[Email],[dbo].[fncomputeage](DOB) from [dbo].[Patient_registration] where [patient_id] = @id end please note dbo.fncompute(DOB) is a function
This program should display the sum, average, product, smallest and largest of the numbers.
Java Code:
//Displays the sum, average, product, smallest and largest of the numbers import java.util.Scanner; public class Practice6 { public static void main( String[] args) { Scanner sc = new Scanner(System.in); System.out.print("Enter an integer: ");
[Code] ....
The problem is when I enter
The first integer: 7 The second integer: 5 The third integer: 9
The program displays "The third integer is the largest and the second integer is the smallest" then displays "The first integer is the largest and the second integer is the smallest". The main method returned to the IF statement in the line 23. How or why?
I'm making a Hangman program for Java, here's my code:
import java.util.Scanner; public class Hangman { /** * @param args the command line arguments */ public static void main(String[] args) { String answerWord = WordList.getWord();
[Code] .....
The Compiler gives me this only error:
Hangman.java:39: error: unexpected type displayWord.charAt(i)=userInput.charAt(0); ^ required: variable found: value
I understand that charAt returns i as a value and not a variable. What do I use to return a variable as I intended?
Okay i have done some research and have found that when using the JOptionPane, when the cancel or x button is clicked, the value is returned as null for the particular JOptionPane. It does not seem to work when I try to code it though, I have tried the following:
Java Code:
public static int getBoardType() { int boardType = 0; String boardInput; boardInput = JOptionPane.showInputDialog(null, "Enter 1 (LongBoard), 2 (Shortboard), or 3 (BoogieBoard)." , "Dwelling Type", JOptionPane.QUESTION_MESSAGE);
[Code] ....
If the "X" button or the Cancel button does in fact return a null value, why is the way I have this set up not working?
If I'm checking using an if statement if a file exists like so:
public boolean export(String envName,String fromFile,String toFile) { Vector<String> vector = new Vector<String>(); File file = new File(fromFile); if(file.exists() && file !=null) { return true; } return false;
If it returns true for existing then how would I do another if statement that would say if file returned true then check said file for an id. If Id exists extract all data associated with that id and store in Vector object. Would it be like this:
Ok here i am trying to pull out all the items in my Product table but all it does it last the row in the table. I have tried using do while but it still does not retrieve the information
Here the the Bean
public class Pageitem { private int id; private String name; private double price; private String description; private Date modifyDate; private int category;}//Has getter Setters and ToString methods for the items
The below method shows that a JOptionPane should display when the result is null, meaning it has not found what I was trying to look for. However only the if statement that finds the query runs:
public void find(Person person) { String query = "SELECT * from employee WHERE last LIKE'" + lastName + "'"; try { statement = connection.createStatement(); resultSet = statement.executeQuery(query);
I've been trying to get a handle on how to populate a jtable with data from my resultset and have found out that using DBUtils is probably the easiest method but unfortunately its not working for me at all. The program runs but the jtable remains empty as ever. I don't understand where I'm going wrong with it. I have import net.proteanit.sql.DbUtils; imported at the top and the jar added in class path. Here is my code:
private void jPanel3FocusGained(java.awt.event.FocusEvent evt) { // TODO add your handling code here: // JDBC driver name and database URL String JDBC_DRIVER = "com.mysql.jdbc.Driver"; String DB_URL = "jdbc:mysql://localhost/new";
There is no permission for me that I can change SQL query(or anything like this), and I've to return the modified ResultSet(not TableModel). I googled a lot to implement AbstractResultSet, but no luck for me. How can I achieve this ?
I am trying to use a custom class in a .jsp page, as part of a course I am taking on Web Technologies.The original version of the jsp page was working fine, until I moved part of the Java code to a separate class.Here is the original .jsp code that is working:
It's always good to keep functions smaller and focused on one behavior. So is this safe:
Java Code:
public Unit findBySql(int id){ Unit unit=null; DbConnectionPool dbPool = DbConnectionPool.getInstance(); HashMap<String, String> conditions = new HashMap<String, String>(); conditions.put("id", String.valueOf(id)); String sql = buildSelect("units", "*", conditions);
[Code] ......
As you can see a pass ResultSet to a function which populates the item. But I also make sure that the ResultSet that the passed object is pointing to is closed, so it doesn't leak resources.
I'm want to call another statement within the same resultSet. But it gives an error that the result set is closed.
public static void updateAlarmStatus(int status) { ResultSet rs = null; database.restartDatabase(); try { rs = database .executeQuery("Select alarmId from alarms where alarmDate = '"
[Code] ....
I googled it and came to know that resultSet is automatically closed if we call another statement within in. I've also tried creating the connection again before the second statement but of no use.
I am trying to get resultset into a string and then use split method to store it in an array but it is not working. i tried to work it seperately as java program but it throws exception "could not find or load main class java."
String ar = "This.is.a.split.method"; String[] temp = ar.split("."); for(int i=0;i<temp.length;i++){
I am building an online quiz. I created a database , bean , controller and jsp. I connected database, wrote query , put resultset in arraylist of object and passed it to jsp. My program runs but arraylist size increases everytime and same question get displayed repeatedly . i cant find the error. Everytime i run the program arraylist size increases. I think it is adding same rows again ang again. here is my code for controller and jsp.
I have a my result set object which has data as shown by the attached image.What i am trying to do is traverse these results and do certain operations. I want my program to do this, if I
I'm just wondering whether it is possible to use images as a button in Java. I have two images that I want to use to create a rollover effect, is this possible? And then I would like to reset my java program when the button is clicked, is this also possible?
