Contexts are obsolete and should not be used. Contexts were introduced in Release 4.0 for high-performance access to frequently required data. Since the introduction of ABAP Objects for Release 4.5, contexts have not been developed further. Since Release 6.40, contexts can be replaced by shared objects .
Tips for Creating Contexts
Reading fewer fields reduces the load on the database
Fewer fields means that the buffer requires less space
The system can then read the buffer more quickly
You can always add more fields later if required.
Tips for Using Contexts
you should always use the SUPPLY command as soon as the key values are assigned. This reduces the risk of deriving obsolete values in the DEMAND statement. You do not need to make a preliminary query to see whether the contents of the key fields have changed, since the system does this itself in the SUPPLY command.
you should always use the DEMAND statement immediately before using the derived values. This is to ensure that you always use up-to-date values.