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Posted by --CELKO-- on 02/02/06 00:39
>> Perhaps though I am missing your point celko. If so, could you be more precise? <<
Just read any book on RDBMS. The Relational model is based on sets.
By definition sets have no ordering. Dr. Codd is a good place to
start.
Thus, an SQL implementationis free to use PHYSICAL storage in any way
it wishes. Contigous storage such as SQL Server is currently using is
only one approach. Teradata uses hashing and can re-arrange physical
storage without telling you. Ingres has several kidns of indexing and
can change the method used based on a statistics. Several other
products will insert new rows over the storage used for deleteed. The
SAND engine assembles rows from compressed bit vectors and has no
physically
contigous storage at all.
You do not know the RM or the SQL standards, so you think that SELECT
TOP 1 is not a dialect, that you must have physically contigous storage
at all, etc. The kind of code you are writing mimicks the way we used
to write for magnetic tape file systems. You need to get more abstract
in your thinking.
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