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In general, when you want to make a slow SELECT... WHERE query faster, the first thing to check is whether you can add an index. All references between different tables should usually be done with indexes. You can use the EXPLAIN statement to determine which indexes are used for a SELECT
Some general tips for speeding up queries on MyISAM tables:
To help MySQL better optimize queries, use ANALYZE TABLE or run myisamchk --analyze on a table after it has been loaded with data. This updates a value for each index part that indicates the average number of rows that have the same value. (For unique indexes, this is always 1.) MySQL uses this to decide which index to choose when you join two tables based on a nonconstant expression. You can check the result from the table analysis by using SHOW INDEX FROM tbl_name and examining the Cardinality value. myisamchk --description --verbose shows index distribution information.
To sort an index and data according to an index, use myisamchk --sort-index --sort-records=1 (assuming that you want to sort on index 1). This is a good way to make queries faster if you have a unique index from which you want to read all rows in order according to the index. The first time you sort a large table this way, it may take a long time.
53)Introduces data mining concepts and techniques.
Data mining is a logical process that is used to search through large amount of data in order to find
useful data. The goal of this technique is to find patterns that were previously unknown. Once these
patterns are found they can further be used to make certain decisions for development of their businesses.
Association rule
Association and correlation is usually to find frequent item set findings among large data sets. Types of association rule:
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1 Multilevel association rule
2 Multidimensional association rule
3 Quantitative association rule
Decision tree learning is a method commonly used in data mining. The goal is to create a model that predicts the value of a target variable based on several input variables.
Clustering
Clustering can be said as identification of similar classes of objects. By using clustering techniques we can further identify dense and sparse regions in object space and can discover overall distribution pattern and correlations among data attributes.
Classification
Types of classification models:
• Classification by decision tree induction
• Bayesian Classification
• Neural Networks
• Support Vector Machines (SVM)
• Classification Based on Associations
Logistic regression
In statistics, logistic regression is a type of regression analysis used for predicting the outcome of a categorical (a variable that can take on a limited number of categories) criterion variable based on one or more predictor variables.
Text mining sometimes alternately referred to as text data mining, roughly equivalent to text analytics, refers to the process of deriving high-quality information from text. High-quality information is typically derived through the devising of patterns and trends through means such as statistical pattern learning.
Web analytics is the measurement, collection, analysis and reporting of internet data for purposes of understanding and optimizing web usage.
54)Organizational foundations of information systems,
General control problems in organizations
Organizational effectiveness is maintained constant control, adaptation of its configuration and proportions to many changes in the external and internal (structure-forming) factors, which include:
· Prices and demand for goods and services, raw materials, labor costs and taxes;
· Bank interest rates;
· Administrative law;
· Production technology, including equipment;
· Number, qualifications, education, the ability of workers;
· Performance of personnel and equipment;
· Production areas, different standards and much, much more.
French engineer and researcher, the ideologue of the classical (administrative) school of Management, Henri Fayol proposed a system of 9 basic management principles that govern the regulatory and behavioral basis of the control system.
They’re:
1. division of labor
2. power and responsibility
3. discipline
4. undivided authority
5. unidirectionality of force (action)
6. combination of individual and common interests
7. remuneration staff of the Organization
8. availability of initiative harmony among the members of the organization
