MM Process Flow, Relevant T-Codes and Tables

MM Process Flow
PR (Purchase Requisition) > Release the PR > RFQ (Request for Qotation) > Quotation > Quotation Comparison > PO > Release the PO > GR (Goods Receiving) > Invoice Verification
The typical procurement cycle for a service or material consists of the following phases:
1. Determination of Requirements
Materials requirements are identified either in the user departments or via materials planning and control. (This can cover both MRP proper and the demand-based approach to inventory control. The regular checking of stock levels of materials defined by master records, use of the order-point method, and forecasting on the basis of past usage are important aspects of the latter.) You can enter purchase requisitions yourself, or they can be generated automatically by the materials planning and control system.
2. Source Determination
The Purchasing component helps you identify potential sources of supply based on past orders and existing longer-term purchase agreements. This speeds the process of creating requests for quotation (RFQs), which can be sent to vendors electronically via SAP EDI, if desired.
3. Vendor Selection and Comparison of Quotations
The system is capable of simulating pricing scenarios, allowing you to compare a number of different quotations. Rejection letters can be sent automatically.
4. Purchase Order Processing
The Purchasing system adopts information from the requisition and the quotation to help you create a purchase order. As with purchase requisitions, you can generate Pos yourself or have the system generate them automatically. Vendor scheduling agreements and contracts (in the SAP System, types of longer-term purchase agreement) are also supported.
5. Purchase Order Follow-Up
The system checks the reminder periods you have specified and - if necessary - automatically prints reminders or expediters at the predefined intervals. It also provides you with an up-to-date status of all purchase requisitions, quotations, and purchase orders.
6. Goods Receiving and Inventory Management
Goods Receiving personnel can confirm the receipt of goods simply by entering the Po number. By specifying permissible tolerances, buyers can limit over- and underdeliveries of ordered goods.
7. Invoice Verification
The system supports the checking and matching of invoices. The accounts payable clerk is notified of quantity and price variances because the system has access to PO and goods receipt data. This speeds the process of auditing and clearing invoices for payment.

Relevant T-Codes
Purchase Order Requisition- ME51N
RFQ to Vendor ------------------- ME41
Raising Quotation -------------- ME47
Comparison of Price ----------  ME49
Vendor Evaluation -------------- ME61
Creation of PO ------------------- ME21N
Goods Receipt with PO ------- MIGO
Goods Receipt without PO --- MBIC
Invoice Verification -------------- MIRO
Goods Issue --------------------- MB1A
Physical Inventory -------------- MI01( Create doc)
MI04 (Enter Count)
MI07 (Post)

Common Tables used by MM
Below are few important Common Tables used in Materials Management Modules:
EINA Purchasing Info Record- General Data
EINE Purchasing Info Record- Purchasing Organization Data
MAKT Material Descriptions
MARA General Material Data
MARC Plant Data for Material
MARD Storage Location Data for Material
MAST Material to BOM Link
MBEW Material Valuation
MKPF Header- Material Document
MSEG Document Segment- Material
MVER Material Consumption
MVKE Sales Data for materials
RKPF Document Header- Reservation
T023 Mat. groups
T024 Purchasing Groups
T156 Movement Type
T157H Help Texts for Movement Types
MOFF Lists what views have not been created
A501 Plant/Material
EBAN Purchase Requisition
EBKN Purchase Requisition Account Assignment
EKAB Release Documentation
EKBE History per Purchasing Document
EKET Scheduling Agreement Schedule Lines
EKKN Account Assignment in Purchasing Document
EKKO Purchasing Document Header
EKPO Purchasing Document Item
IKPF Header- Physical Inventory Document
ISEG Physical Inventory Document Items
LFA1 Vendor Master (General section)
LFB1 Vendor Master (Company Code)
NRIV Number range intervals
RESB Reservation/dependent requirements
T161T Texts for Purchasing Document Types

Reference
https://www.sdn.sap.com/irj/sdn/thread?messageID=2587232#2587232
https://www.sdn.sap.com/irj/sdn/thread?messageID=2757752#2757752
https://www.sdn.sap.com/irj/sdn/thread?messageID=2790858#2790858

http://www.sapgenie.com/abap/tables_mm.htm
http://www.sap-img.com/sap-download/sap-tables.zip
http://www.allsaplinks.com/material_management.html
http://www.training-classes.com/course_hierarchy/courses/2614_SAP_R_3_MM_Invoice_Verification_-_Rel_4_x.php
http://www.sapfriends.com/sapstuff.html

http://help.sap.com/printdocu/core/Print46c/en/data/pdf/PSMAT/PSMAT.pdf
http://help.sap.com/printdocu/core/Print46c/en/data/pdf/CAARCMM/CAARCMM.pdf
http://help.sap.com/printdocu/core/Print46c/en/data/pdf/MYSAP/SR_MM.pdf
http://help.sap.com/printdocu/core/Print46c/en/data/pdf/LOMDMM/LOMDMM.pdf
http://help.sap.com/printdocu/core/Print46c/en/data/pdf/BCBMTWFMMM/BCBMTWFMMM.pdf
http://help.sap.com/printdocu/core/Print46c/en/data/pdf/MMIVMVAL/MMIVMVAL.pdf
http://help.sap.com/printdocu/core/Print46c/en/data/pdf/MMWMLVS/MMWMLVS.pdf
http://help.sap.com/printdocu/core/Print46c/en/data/pdf/MMISVE/MMISVE.pdf

http://help.sap.com/printdocu/core/Print46c/en/data/pdf/PSMAT/PSMAT.pdf
http://help.sap.com/printdocu/core/Print46c/en/data/pdf/CAARCMM/CAARCMM.pdf
http://help.sap.com/printdocu/core/Print46c/en/data/pdf/MYSAP/SR_MM.pdf
http://help.sap.com/printdocu/core/Print46c/en/data/pdf/MYSAP/SR_MM.pdf