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8 – ObfuscationLEFT(Identification_Value,4) AS Identification_ValueFROMdbo.Borrower_Identification;GOListing 8-10: Returning a truncated value.EncodingEncoding is a technique in which a series of characters is used to representanother value. This technique can be used to camouflage sensitive data, sincethe code used has no meaning outside the system in which the code is defined.NOTE:There are many benefits to encoding, beyond securing sensitive data, such asovercoming language barriers when working in an international environmentand providing an expedient means of entering data.Encoding is a practice that is found in abundance in the health care industry.The World Health Organization maintains the International Classification ofDiseases (ICD), which is an industry standard that defines codes that representdiseases and health problems. These codes are used in health records and deathcertificates. For example, the ICD code for bacterial pneumonia is J15.9.In the establishment of foreign keys in the HomeLending database we have, ata basic level, implemented encoding. The Loan table, for example, containstwo columns that are named Purpose_Type_ID and Mortgage_Type_IDas illustrated in Figure 8-1 (for a full representation of the HomeLendingschema, see Figure 2-1, in Chapter 2).Figure 8-1: Loan table with Foreign Key Relationships184