Hi,
If the nature of the data to be stored in a database is like the
following, what is a more efficient method of storing them?
For a table in the database, there are a large number of possible
fields (mostly of type integer, float and strings), but each row has a
different set of fields available and other fields are N/A. Field sets
of rows overlap some but still have much non-overlaping. For example,
all possible files are F1, F2, ..., F50. Row 1 only has F1, F6, F8, ...,
F47, F49. Row 2 has F1, F2, F5, F6, F10, ..., F46, F49, F50. And so on. If
the table is created with a schema including all possible files (F1
through F50), many fields in the database is just empty which is not very
efficient. What is a better way of storing this kind of data? Is
document-oriented database (XML) better? Are there better ones than XML?
Thanks,
Stan

On Tue, 10 Feb 2004, Stanley Yao wrote:

different tables. Sience it's science data, all fields are not clearly
dividable into groups; they are equally part of the whole row. It is
better to store all fields in the same table.
Thanks,
Stan

Stanley Yao wrote:
The idea that n-coulmns of n-bytes is inefficient per se, is deluded. This
is an implementation issue of the specific database in question. It is not
necessarily wasted and it is not necessarily inefficient. In fact this I
suspect the idea is only applicable to the most mindboggingly primitive
database engines.

I need to know more about what the columns mean to determine whether your
design is logically valid though, as you give no udesful information
Dr. Dweeb.

Dr. Dweeb wrote:
Oops, I meant to say "... n-columns of n-bytes containing no data is ..."