The driver supports the MinKey and Maxkey special values and, by default, maps them to the VARCHAR JDBC Data type during relational mapping. Note that MinKey and MaxKey values are static and return the same data whenever they are queried. The following are the respective values returned by the driver:
  • MinKey: {“$MinKey”:1}
  • MaxKey: {“$MaxKey”:1}

MinKey and MaxKey are special values used internally by MongoDB that do not have a counterpart in SQL. Therefore, they cannot be used in Where clauses for comparisons.

Note: The DatabaseMetaData.getTypeInfo() method does not return results for the MinKey and MaxKey data types.