Oracle version 9 introduced interesting new data types, which allow developers to declare a variable that can contain any type of data. The data types are ANYDATA for a single item, ANYDATASET for a TABLE or VARRAY of data, and ANYTYPE, which describes the type of data stored in ANYDATA or ANYDATASET variables and columns. These data types are important for processing XML data stored in the database, or for Advanced Queues. The documentation mentions that the ANYDATA data type can be used to serialize objects, but there are very few examples of this concept.
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