Any data longer than the specified length will be split between the data table and external overflow buffers. The table structure shown in the example would benefit greatly from the creation of some indices . Such a field would normally be defined as the primary key. Similarly, a common query may be to access an employee based on the combination of the first and last names. The user is not required to specify any special values in the query to ensure the indices are used to increase performance.
Sequences provide a mechanism via which a sequence value can be maintained by the mSQL server.
A sequence is associated with a table and a table may contain at most one sequence. The value of a sequence would decrease by 5 each time it was accessed if it was defined with a step of -5. The Drop clause is used to remove a definition from the database. It is most commonly used to remove a table from a database but can also be used for removing several other constructs. In 2.0 it can be used to remove the definition of an index, a sequence, or a table.