SAP ABAP Technical Questions (Data Dictonary)

What is data Dictionary?
What is the difference between open sql & native sql ?
Difference between Pooled, cluster & transparent tables?
What is Primary key, foreign key ? what is primary index?
secondary index?
how many indexes can be created for a table?
what is a value table?
what are the components of a table?
what is a domain?
what is a data element?
what is data class?
can you create a table with out a data element?
can you create a field with out a data element?
What approach you prefer for creating a table?
Give few names of cluster tables in sap?
Give few names of pooled tables in sap?
give few names of transparent tables?
what is a buffer and how many types?
what is table maintenance generator and how to create that?
What is the transaction code? How to add new fields to a standard sap table ?
How many types of table joins are there? difference between inner join & outer join?
Difference between "select * from mara" and "select single * from mara"?
what is a match code ? Lock objects ? what are views?
what are logical tables/database?
what is the difference bet'n table and a structure?