Object Name	Function of the object	E.g.
_ALL	Underlying table with all the values	PO_DISTRIBUTIONS_ALL
_B	Base of underlying table, same as _ALL	MTL_SYSTEM_ITEMS_B
_TL	Language translation table with translation of descriptive fields in different languages	FND_RESPONSIBILITY_TL
_VL	View based on translation table,are views for multi language tables which combines the row of the base table with the corresponding row of the _TL table where the LANGUAGE = USERENV('LANG').
_V	tables are the views created on base tables	PJM_PROJECTS_ALL_V
_BASIC_V	View on top of the Basic table
_DFV	Descriptive Flex Field related view, it will have the defined values as Column names instead of generic attribute 1, ..2
_KFV	Key Flex Field views contain the concatenated fields as it would be displayed to the user. For e.g. A field may consist of Division, Department and Account fields and the KFV will have the concatenated values.eg.GL_CODE_COMBINATIONS_KFV
_S	are sequences, used for finding new values for the primary key of a table.
_A	are Audit Shadow Tables
_AVN	and _ACN are Audit Shadow Views (when data was changed, and with what values

SELECT * FROM dba_objects WHERE object_name LIKE 'MTL%_KFV' AND object_type = 'VIEW'可以见MTL下的KFV主要包括Item,SO,Locator,Categories..

MTL_SYSTEM_ITEMS_B_KFV

MTL_SYSTEM_ITEMS_B1_KFV

MTL_SALES_ORDERS_KFV

MTL_ITEM_LOCATIONS_KFV

MTL_ITEM_CATALOG_GROUPS_B_KFV

MTL_GENERIC_DISPOSITIONS_KFV

MTL_CATEGORIES_B_KFV