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Different databases, different ways of specifying the query and various indexing methods have been tried.

September - October

The spatial extensions are no longer used since performances are disappointing especially when indexes need to be rebuilt.

Selection of events located within a cone is implemented more accurately.

A typical result with MySQL is shown here.

January - June

With a pretty small number of events and using the geographical modules available in the database procucts a first evaluation has been made.

Sample Data are stored in a relational database. Events data are kept in a table.
A perl script is run to retrieve events located in a region defined by ra_max, dec_max, ra_min,dec_min. (typically 32x32 degrees).
The time spent by the query as well as the number of events found are kept.
The query is launched 100 times, statistics are output.

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