Here's a comprehensive list of function modules with descriptions of what they do. 

Activating table and config changes is described in OSS note 1916

Internal table is a very important concept in ABAP/4 programming. For a novice programmer, it is essential that He / She understands the underlying concept of internal table. This documentation explains internal table in a very precise and in simple words. It explains from the basics of an internal table and gradually navigating to its features and operations.

I have explained Standard, Sorted and Hashed tables and its operations separately and in the respective order. My suggestion towards a clear understanding of internal table from this document is to have a clear idea of Standard Table first and practice and then move to Sorted and Hashed Tables.

For your convenience I have isolated the system fields used for internal tables and defined few terms in Glossary that are necessary for understanding Internal Tables. I would like to thank www.erpgenie.com for providing online documentation on ABAP/4 for young ABAP’ers like me. Believe this document will provide a clear understanding of Internal Table. Happy ABAPing.

Some useful reports:

• RPR_ABAP_SOURCE_SCAN Search ABAP code for a string. Has many more options for selecting the ABAPs to search than RSRSCAN1 or RKCTSEAR.

• REKH0004 SAP demo program that shows how to do 2D, 3D, and 4D graphics.
• ...
  

For instance, I set this up in a multi-language environment when you have a code and text combination you want to set up. Typically, you have to set up two tables: One with just the valid codes i.e. Zxxx where the only field is the code field, the second is ZxxxT which contains the code and language as the primary index with the description as the data field. In this case, then you usually define a view H_Zxxx which is a join on these two tables. The key thing is that the Foreign Key definition for the code field in the ZxxxT must have the must have the type "Key Fields of a Text Table". This results in the Table Maintenance generator (SM30) generating a screen that allows you to maintain the code and description together for the system language.

In a related note, to set up a customer transaction for a Table Maintenance generated dialog, use SE80 and enter the function group used for the table maintenance dialog. Then Create a transaction (Zxxx) of type parameter. Fill in text, specify Transaction SM30, click on "skip initial screen" and set up default values of VIEWNAME set to Zxxx and UPDATE set to X.

Use 4 single quotes to find one quote in a string. The following code snippet will replace a single quote with a double quote.

replace '''' with '"' into field

*EJECT - If you put *EJECT at the start of a line, it will force a new page when you print your source code. This comes in real handy when you would like to have subroutines start at the top of a new page.

*$*$* - By placing *$*$ at the beginning of a comment line will lock the line for editing. You are able to edit the line until you hit the enter key.

Starting in Version 4.5, SAP allows easy customizing of the infotype screens by providing customers with subscreens and customer specific includes for infotypes.

Transaction PM01 is used to customize the infotype, and the online help is reasonably useful in walking you through the steps needed to add your own fields to the infotype.

Before calling DOWNLOAD or WS_DOWNLOAD, do a perform SET_TRAIL_BLANKS(saplgrap) using 'X'.
To set the length of each record including your blanks add this code: perform SET_FIXLEN(saplgrap) using '0' '100'