Dear List

Thank you to everyone who pointed me towards SQL Query, especially Russell
Lawley, Johnathan Stokes, Dr. Franz-Josef Behr and Mike Saunt. 
The query syntax is "select polyname, crimetype, count(*) from Polygontable,
pointtable where
polygon contains point group by polyname, crimetype"

We found that selecting 22,700 of 45,000-odd points lay within 210 polygons,
and sorting within the polygons was very slow. In the end I set it running
and went home. I have considered what could be done to optimise running, but
this may have to wait until it is a more regular process in order to justify
the effort. 

Thanks again to everyone. 

Georges Sen-Gupta

Senior Information Officer, Crime Unit
Cheif Executive's Department
London Borough of Lambeth
Town Hall
SW2 1RW



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