The PCI Standard has this concept at its core. Clear card data is stored in clear text – which poses a huge security risk. It is vital that all occurrences of clear card data are located and either cleaned up or secured. Read this white paper to learn about the scope of the problem and the best practices for scanning databases. Read the white paper by clicking here to learn more about how to scan databases and how to deal with the problem of clear credit card data in a database using a scanning tool.”]
Source: https://www.bankinfosecurity.com/whitepapers/scanning-databases-for-credit-card-information-w-703