Change TEXT field to FLOAT? Needed for Lat/Lang Radius search

[Erik Richter]

EDIT2: Actually I've been stupid, mixed up Max and Min for the negatives. Everything works now - pretty slow tho.. If anyone has tipps on making queries faster (talking 1 mio pages) Let me know!

 

Hey guys,

Is it possible to change fieldtype text to float for a live website?

I have about 1 Mio pages with Lat/Long coordinates (from geocoding) stored in a TEXT field. 

Works perfectly for displaying on maps etc. - but now  I wanted to implement a query filtering for radius (min/max gets calculated correctly before).

This $pages->find does not find results, and I suspect it is because some values are negative? (Lang: -80.45550 for example).

$pages->find("lat>=$minlat, lat<=$maxlat, lang>=$minlng, lang<=$maxlng")   -> fields are TEXT fields.

It looks like the Comparison operator is not working here. Any tips on this? Thank you!!

EDIT: I just changed the fieldtype to Float via Tracy Adminer... no change. The operators are still not giving any results. Strange. Hopefully anyone here has an idea!