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Hands-On Microsoft SQL Server 2008 Integration Services part 49. Deploy and manage high-performance data transformation solutions across your enterprise using the step-by-step techniques in this fully revised guide. Hands-On Microsoft SQL Server 2008 Integration Services, Second Edition explains the tools and methods necessary to extract conclusive business intelligence from disparate corporate data. Learn how to build and secure packages, load and cleanse data, establish workflow, and optimize performance. Real-world examples, detailed illustrations, and hands-on exercises are included throughout this practical resource. . | 458 Hands-On Microsoft SQL Server 2008 Integration Services column and uses its internal algorithms and statistical models in line with the options you ve selected to generate the output results. The output of this transformation contains only two columns Term and Score by default. The Term column contains the extracted term while the Score column contains the number of times that term is found in the input column. To meet its objective of reading from an input column and writing to an output this transformation supports one input and one output along with one error output. This transformation can extract terms from the input column that of either the DT_WSTR or DT_NTEXT data type. Generally you will use this transformation as the last transformation in that branch of the data flow as it doesn t let the input columns pass through. However it does provide an output that contains only the two resulting output columns. When you open Term Extraction Transformation Editor you will see the following three tabs Term Extraction In this tab you can select an input column from the list of Available Input Columns from which you want this transformation to extract a term. You also can specify the names for the two output columns in this tab which by default are Term and Score. Exclusion You can choose to use exclusion terms by clicking the Use Exclusion Terms check box which tell the transformation to exclude some of the terms from extraction. While you are trying to build a meaningful list of terms that you can use for data mining purposes you may want to exclude certain terms because they are appearing everywhere and causing you to lose focus from the key terms. You can specify the exclusion terms in a lookup table that must be in SQL Server 2000 or later editions or Microsoft Access. This lookup operation works in a fully precached mode which means that the transformation loads the exclusion terms from the lookup table into its private memory before it starts extracting .
