there is not events in internal table..
but you can declare the internal tables in different ways..
Key access to a standard table uses a linear search. This means that the time required for a search is in linear relation to the number of table entries.
You should use index operations to access standard tables.
Defines the table as one that is always saved correctly sorted.
Key access to a sorted table uses a binary key. If the key is not unique, the system takes the entry with the lowest index. The runtime required for key access is logarithmically related to the number of table entries.
Defines the table as one that is managed with an internal hash procedure
You can only access a hashed table using the generic key operations or other generic operations ( SORT, LOOP, and so on). Explicit or implicit index operations (such as LOOP ... FROM oe INSERT itab within a LOOP) are not allowed.
A table that can be accessed using an index.
Index table is only used to specify the type of generic parameters in a FORM or FUNCTION. That means that you can't create a table of type INDEX.
Standard tables and sorted tables are index tables.
Any table is only used to specify the type of generic parameters in a FORM or FUNCTION. That means that you can't create a table of type ANY.
Standard, sorted and hashed tables belongs to ANY tables
I think you are talking about the control conditions in an internal table.
They are as follows:
AT - Control breaks with internal tables
1. AT NEW f.
2. AT END OF f.
3. AT FIRST.
4. AT LAST.
In a LOOP which processes an internal table, you can use special control structures for control break processing. All these structures begin with AT and end with ENDAT. The sequence of statements which lies between them is then executed if a control break occurs.
You can use these key words for control break processing with internal tables only if a loop is actively processing an internal table and reference is to the innermost currently active loop.
The control level structure with internal tables is static. It corresponds exactly to the sequence of columns in the internal table (from left to right). In this context, the criteria according to which you sort the internal table are unimportant.
At the start of a new control level (i.e. immediately after AT), the following occurs in the output area of the current LOOP statement:
All character type fields (on the right) are filled with "*" after the current control level key.
All other fields (on the right) are set to their initial values after the current control level key.