The data mining is the essential point of data combination for business intelligence. Now-a-days, there has been emerging trends in database to discover useful patterns and/or correlations among attributes, called data mining. This paper presents the data mining techniques like classification, clustering and associations analysis which include algorithms of decision tree (like C4.5), rule set classifier, kNN and Naïve Bayes, clustering algorithms (like k-means and EM) machine learning (like SVM), association analysis (like Apriori). These algorithms are applied on data warehouse for extracting useful information.