-`Segment`: The memory structure of storing a piece of data which supports concurrent insertion, deletion, query, index loading, monitoring and statistics
-`Schema`: Definition of collection data format, including
-`vector<FieldMeta>`: Order list of FieldMeta
-`isAutoId`: If set to True , default primary field is `RowId` and it is auto generated
-`isAutoId`: If set to True , the default primary field is `RowId` and it is auto generated
-`primaryKey`: (When `isAutoId = False`) Specify primary key field
-`FieldMeta`: Field properties, including
-`DataType`: Data type, including Int8...Int64, Float, Double, FloatVector, BinaryVector and String later