VMap
A Vertica map (VMap) data format is used to store unstructured or semi-structured data, primarily in flex tables. Columnar tables can also include a VARBINARY
column containing a VMap. Flex tables always include a __raw__
column to contain a VMap. Some flex-related functions, such as EMPTYMAP
or MAPJSONEXTRACTOR
return a VMap value.
A VMap consists of a varbinary blob containing raw data. This data is processed for structure or interpretation during loading or data extraction. After processing, the VMap data includes a dictionary-style lookup of key::value
pairs. The keys in VMap data are Virtual Columns.