database

How I can Optimize this mySQL transaction within java code?

Dear All, I am new to MySql database. I've large table(ID,...). I select ID frequently with java code and.And that make a heavy load on transaction select from tableName where ID=someID notes: 1.Database could be 100,000 records 2.I can't cache result 3.ID is a primary key 4.I try to optimize time needed to return result from que...

Is Cassandra database row size limited by available memory?

I'm working with very long time series -- hundreds of millions of data points in one series -- and am considering Cassandra as a data store. In this question, one of the Cassandra committers (the über helpful jbellis) says that Cassandra rows can be very large, and that column slicing operations are faster than row slices, hence my quest...

"Thread was being aborted" 0n large dataset

I am trying to process 114,000 rows in a dataset (populated from an oracle database). I am hitting an error at around the 600 mark - "Thread was being aborted". All I am doing is reading the dataset, and I still hit the issue. Is this too much data for a dataset? It seems to load into the dataset ok though. I welcome any better ways ...

How to point to other table's ID with hibernate?

The problem: let's say I have two tables Client, and Product, in which Client has its primary key and a column called products (that points to pk's in Product table)... ok, if I need products to point only one row, it's nice, but if I need it to point for... 1000 rows in Product table, the products column would have to be larger enough.....

Is there a standard pattern for scanning a job table executing some actions?

(I realize that my title is poor. If after reading the question you have an improvement in mind, please either edit it or tell me and I'll change it.) I have the relatively common scenario of a job table which has 1 row for some thing that needs to be done. For example, it could be a list of emails to be sent. The table looks somethi...

Tools to work with App Engine data dumps

Using the bulkloader.py utility you can download all data from your application's Datastore. It is not obvious how the data is stored, however. From the looks of it, you get a SQLite file with all data in binary format in a single table: sqlite> .tables bulkloader_database_signature result sqlite> .schema result CREATE TABLE resul...

MySQL Frontend that displays foreign rows nested within a table's rows?

I once came across a MySQL Frontend app that displayed foreign linked rows within the parent row, if for instance the Client table has a foreign key to the Suburb table: Do you know of any Frontend that can do this? ...

How can I view my BO report SQL in database (I mean in any of the BO table)

I need to view my "BO report SQL" in database rather from web through edit query. How can I achieve this? Please help me out and provide me the steps. It may be in BO repositry OR ...

How to store dynamic references to parts of a text

In fact, my question concerns an algorithm. I need to be able to attach annotations to certain parts of a text, like a word or a group of words. The first thing that came to me to do so is to store the position of this part (indexes) in the text. For instance, in the text 'The quick brown fox jumps over the lazy dog', I'd like to attach...

How to monitor the change of the database so as to flush the treeview?

target: whenever the table in the database changes, the treeview will reload the new contents of the table. Is there any good methods to solve this problem? thank u ...

Filling data in FormView from different tables

Hi, I am using a FormView in an online quiz page for displaying the questions and RadioButtons (for answers) http://stackoverflow.com/questions/2438219/online-quiz-using-asp-dot-net Now, I need to pick the questions according to a TestID and a particular Set of that Test. The testid and the set_number would be passed using Session...

Transferring data from one list box to another c#

Hi, Ok so I have 2 list boxes one is connected to a database the other isnt. I want to be able to send the selected item from the listbox connected to the database to the one that isnt. Ive written this code listBox2.Items.Add(listBox1.SelectedItem); But instead of copyin the item i get " System.Data.DataRowView Anyone havin any ...

Compare Database container and class container

I am using a SQL Server database in my current project. I was watching the MVC Storefront videos (specifically the repository pattern) and I noticed that Rob (the creator of MVC Storefront) used a class called Category and Product, instead of a database and I have notice that using LINQ-SQL or ADO.NET, that a class is generated. Is there...

Many to many table design question

Originally I had two tables in my DB, [Property] and [Employee]. Each employee can have one "Home Property" so the employee table has a HomePropertyID FK field to Property. Later I needed to model the situation where despite having only one "Home Property" the employee did work at or cover for multiple properties. So I created an [Emp...

Speeding up inner-joins and subqueries while restricting row size and table membership

I'm developing an rss feed reader that uses a bayesian filter to filter out boring blog posts. The Stream table is meant to act as a FIFO buffer from which the webapp will consume 'entries'. I use it to store the temporary relationship between entries, users and bayesian filter classifications. After a user marks an entry as read, it w...

Fiscal year handling strategies in database design

By fiscal year I mean all the data in the database (in all tables) that occurred in the particular year. Lets say that we are building an application that allows user to choose from different years. What way of implementing this would you prefer, and why: Separate fiscal year data based on multiple separate database instances (for exa...

error in mysql syntax in vb.net

I get this error, while I'm testing the code below: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '[student](ID, LASTNAME, FIRSTNAME, SCHOOL) VALUES ('333', 'aaa', 'aaa', 'aaa')' at line 1 I just recycled the code that I used in manipulating ms sql...

Visual Representation Of Database Schema

is there some standard about how to graphically represent database schemas? Is UML a defacto standard for this? Also, is there some free tool that can help me convert an sql file (basically bunch of CREATE TABLE queries) into some nice graph (UML or not UML)? ...

Is it possible to listen to relational database update?

Is it possible to listen to relation database update? For example, my web app want to send data update to client through Comet technology. I can have the program to poll the database periodically, but that would not be performant and scalable. If app can hood to a "event handler" of database, then app can get notification every time gi...

In MySQL, how do I create a column with a foreign key?

A column with a foreign key to another table's column. How do I do that? ...