Support sparse serialization

[den818]

No description provided.

[den818]

classDiagram

class Serialization {
    <<Interface>>
    GetKind()
    LoadPrefix()
    LoadBody()
    SavePrefix()
    SaveBody()
}


SerializationDefault~ColumnType~ --|> Serialization 

SerializationSparse --|> Serialization

SerializationSparseT~ColumnType~ --|> SerializationSparse

class Column {
<<Interface>>
     Load()
     Save()
     LoadSerializationKind();
    SaveSerializationKind();
    SetSerializationKind();
    GetSerialization();
    HasCustomSerialization();
}

ColumnSome --|> Column

ColumnSome  --> SerializationDefault~ColumnType~

ColumnSome --> SerializationSparseT~ColumnType~ 

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[Enmk]

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