Table2 Billing

Table VBRK

*VBRK is Sales Invoice table.
VBRK is used for saving Sales Invoice Header data, Credit Memo Header data, etc.
Some fields which i will explain, have special attention for me.

VBELN = Billing Document
FKART = Billing Type
FKTYP = Billing category
VBTYP = SD document category
M = Invoice
N = Invoice Cancellation
O = Credit Memo
P = Debit Memo
S = Credit Memo cancellation
etc
KURRF = Exchange rate for FI postings
WAERK = SD document currency
VKORG = Sales Organization
VTWEG = Distribution Channel
BZIRK = Sales district
KNUMV = Number of the document condition
FKDAT = Billing date for billing index and printout
ZTERM = Terms of payment key
NETWR = Net value in document currency
KUNRG = Payer
KUNAG = Sold-to party
SFAKN = Cancelled billing document number
It is only filled if the document is the document cancel and SFAKN is the document billing reference
FKSTO = Billing document is cancelled.
FKSTO, it explain that the document has been cancelled.
so, if you want to know which document has cancelled the billing,
you have to search VBRK table again which field is VBRK.SFAKN = VBRK.VBELN

*VBRP is sales invoice detail table.
VBELN = Billing Document
POSNR = Billing item
FKIMG = Actual Invoiced Quantity
VRKME = Sales unit
MEINS = Base Unit of Measure
NETWR = Net value of the billing item in document currency
VGBEL = Document number of the reference document (Related with table LIPS)
VGPOS = Item number of the reference item (Related with table LIPS)
AUBEL = Sales Document
AUPOS = Sales Document Item
MATNR = Material Number
SPART = Division
VKGRP = Sales group
VKBUR = Sales office