In Linux, if a program crashes, it often dumps a “core ” into your home directory. This is accompanied by an appropriate message. A core is a memory image and is a debugging tool. If you are a user who does not intend to debug the program, you may simply delete the core : Rm [...]
Continue reading → Sometimes, a simple GROUP BY clause just isn’t enough in a query. Once you generate a report of, let’s say, average salary by department or the standard deviation of sick days by job title, you often must run a second query that calculates the average salary or standard deviation across the entire set of employees. [...]
Continue reading → Over the past four decades the computer industry has experienced four generations of development, physically marked by the rapid changing of building blocks from relays and vacuum tubes (1940-1950s) to discrete diodes and transistors (1950-1960s), to small- and medium-scale integrated (SSI/MSI) circuits (1960-1970s), and to large- and very-large-scale integrated (LSI/VLSI) devices (1970s and beyond). Computer [...]
Continue reading → Data mining has many and varied fields of application some of which are listed below. Retail/Marketing 1. Identify buying patterns from customers 2. Find associations among customer demographic characteristics 3. Predict response to mailing campaigns 4. Markets analysis Banking 1. Detect patterns of fraudulent credit card use 2. Identify ‘loyal’ customers 3. Predict customers likely [...]
Continue reading → 1.Growing Data Volume The main reason for necessity of automated computer systems for intelligent data analysis is the enormous volume of existing and newly appearing data that require processing. The amount of data accumulated each day by various business, scientific,and governmental organizations around the world is daunting. 2. Limitations of Human Analysis Two other problems [...]
Continue reading → There are many data mining systems available or being developed. Some are specialized systems dedicated to a given data source or are confined to limited data mining functionalities, other are more versatile and comprehensive. 1. Classification according to the type of data source mined: this classification categorizes data mining systems according to the type of [...]
Continue reading → The kinds of patterns that can be discovered depend upon the data mining tasks employed. By and large, there are two types of data mining tasks: descriptive data mining tasks that describe the general properties of the existing data, and predictive data mining tasks that attempt to do predictions based on inference on available data. [...]
Continue reading → In principle, data mining is not specific to one type of media or data. Data mining should be applicable to any kind of information respiratory. However, algorithms and approaches may differ when applied to different types of data. Indeed, the challenges presented by different types of data very significantly. Data mining is being put into [...]
Continue reading → Although the entire process is commonly called “calibration” it is actually a two-part procedure: adjusting the monitor, which is also called “calibration”, and creating a monitor profile for the specific monitor being used. When the two steps are done correctly, the chances of coming up with accurate output increase significantly. Every monitor displays color differently. [...]
Continue reading → One-stop solution for custom flash drives, computer memory and more–>> Gone are the days of mundane compact disks and floppies, today computer memory has taken on an all-new form. Those of you who are thinking of the ordinary Universal Serial Bus are also a step behind. Custom [...]
Continue reading → OEM automatically alert the DBA, through an e-mail message or page, to error conditions or conditions that may signal an impending error. Using OEM’s Event Manager, accessible as one of the nodes in the OEM Navigator pane, the DBA can monitor a variety of error conditions, such as an abnormal termination of the Oracle instance [...]
Continue reading → The alert log file grows in size slowly but without limit. After a few weeks, it can become cumbersome to review the file, so it’s a good idea to archive or delete the file on a periodic basis. The alert log file can be safely renamed or deleted, even when the database is up and [...]
Continue reading → The alert log file is a grab bag of messages about the state of the database instance. It contains entries about significant database events, such as database startup and shutdown, nondefault initialization parameters, ALTER SYSTEM commands, and various errors. Alert Log File : A text file that contains entries about significant database events, such as [...]
Continue reading → ICMP ( INTERNET CONTROL MESSAGE PROTOCOL) messages are divided into two broad categories : error-reporting messages and query messages. The error reporting messages report the problems that a router or a host (destination) may encounter when it processes an IP packet. They would report back the problem back to the IP module at the sending system. [...]
Continue reading → There are five different IP address classes: A,B,C,D AND E. These are designed to cover the needs of different types of organization. The first few bits of the 32 bit IP address determines the type of address class to which IP address belongs. Class A If the first bit is 0 then the given address [...]
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