Package containing mappings for column (JDBC) types. These mappings will be mapped via the MappingManager to the various java type mappings in org.datanucleus.store.rdbms.mapping.java

These are column (JDBC) types, and probably most of them are atomic types mapping to atomic java types

Mappings map persistent java fields in persistable classes to columns in RDBMS tables. Mappings are also used to map "non-fields" in persistable classes to columns in RDBMS tables. A class using datastore identity does not have java fields representing primary-keys in RDBMS tables, but as said earlier a Mapping is also applied to "non-fields". Therefore, a Mapping is applied to:

• persistent java fields
• datastore identity (primary-key columns)
• optimistic columns (columns with version numbers)
• index columns (columns indexing an ordered list)
• owner columns in unidirectional inverse relationships
• adapter columns (additional column added as primary key when the existing columns have datatype not allowed, by database limitation, to be part of the primary key)

In addition to the representation of columns in tables for persistable classes, column mappings are also used for representing columns in queries.