For now it suffices to know that an ABAP program's Brother Cell Phone List runtime environment is in the Application Server's memory. Tier- III: This is where the database resides. SAP has been built in a database agnostic way. There are a list of databases Brother Cell Phone List supported by SAP ( For example, Oracle, Informix, DB2, Max DB, SQL Server etc ) and as long as you use one of those databases in tier-III SAP will work. Now, we all know Brother Cell Phone List that each of these databases have their own versions/flavors of SQL. So when SAP's Application Brother Cell Phone List server interacts with the database layer, it talks via the "Database Interface" or simply DBIF.
The task of DBIF is to ensure that it converts SAP's Open SQL into Brother Cell Phone List native SQL understandable by the corresponding database. Without going much further into SAP's architecture, let's start by creating a database table in SAP. Let's try to create a database table "Customer" as follows. Database Table: Database Table Name ZCUST Database Table Description Customer Database Table Fields CUSTNO CUSTNAME That's a very simple database table.
You might have immediately noticed a peculiarity. Why did I define the database table name as "ZCUST" as opposed to saying "CUST"? To understand this, we have to first understand the concept of SAP Namespace. SAP Namespace: SAP reserves the right to create new programs starting with the letter 'A' through 'X' SAP gives its customers the right to create new programs starting with either the letter 'Y' OR 'Z' SAP gives its partners special names spaces. This is a Brother Cell Phone List very important concept. Imagine a scenario when SAP is implemented in a company say 'Johnson & Johnson' with lots of customization in Version 4.7. Now, J&J wants to upgrade SAP to ECC 6.0.