While SAP doesn’t provide real technical documentation, you can still do a lot to get the information about SAP data model and the sources of data for your programs. I have written a short guide once describing many tricks you can do if you have no idea where the data is coming from. It is published as one of the articles in the ABAP Knowledge Corner from Richard Harper. Apart from that, lots of information is stored right in the SAP system, as standard documentation for programs, functions and ABAP Dictionary objects. For the function modules’, the best way is to use the www.se37.com – a searchable library of documentation. If you want to (try to) get a document from SAP for a database table, here’s the trick: you run the report RSSDOCTB, select the output to be printed on screen and in the popup window (coming after F8 – Run) check all the checkboxes to get the documentation not only for the table but also for relationships and data elements. If you are lucky enough, meaning that normally all older tables (master data and core transaction data tables) are more or less documented, you get a report looking similar to the sample below, that can be stored in a local file. Long time ago I even wrote a program that reprocessed the resulting file into HTML to produce hyperlinked version for many tables.
MARC Material Master: C Segment Application class MG Table class TRANSP SQL-Tabelle Last change by SAP Date 04/09/1996 ______________________________________________________________________ Technical settings data class: APPL0 size category:4 buffering type: ______________________________________________________________________ Table structure Field name K Type Length Data el. Domain Text ______________________________________________________________________ MANDT X CLNT 3 MANDT MANDT Client MATNR X CHAR 18 MATNR MATNR Material number WERKS X CHAR 4 WERKS WERKS Plant PSTAT CHAR 15 PSTAT PSTAT Maintenance status LVORM CHAR 1 LVOWK XFELD Deletion flag for all material data of a plant BWTTY CHAR 1 BWTTY BWTTY Valuation category XCHAR CHAR 1 XCHAR XFELD Batch management indicator (internal) MMSTA CHAR 2 MMSTA MMSTA Material status from MM/PP view MMSTD DATS 8 MMSTD DATUM Date as from which MM/PP status is valid (deactivated) MAABC CHAR 1 MAABC MAABC ABC indicator ... Relationships Field name Checks fromDependencyCardinality Text ______________________________________________________________________ MANDT T000 KEY CN Client MATNR MARA KEY CN WERKS T001W KEY CN BWTTY T149C REF CN MMSTA T141 REF CN EKGRP T024 REF CN AUSME T006 REF CN Unit of measure DISPR MDIP REF CN MRP profile DISMM T438A REF CN MRP type DISPO T024D REF CN Disponent DISLS T439A REF CN Lot size ... Data element BESKZ Domain BESKZ _______________________________________________________________________ Procurement type Definition Indicator that defines how the material is procured. The following procurements types are possible: o The material is produced in-house. o The material is procured externally. o The material can be both produced in-house and procured externally. Checks Lower limit Upper limitValue description __________________________________________________________________ E In-house production F External procurement SPACE No procurement X Both procurement types