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I’m trying to export large (e.g. 16M rows) SQL Server 2008 views for eventual import into MySQL. The underlying setup for these views is bizarre: A SELECT for a single row can take over two minutes, a SELECT * FROM view with no WHERE clause is much faster, but still too slow to finish an [...]

Another post from my sql abominations series. I’m running this on MySQL 5 particularly.
Assume you have a table of locations with Latitude and Longitude for each one. In my case the table is “station”, primary key being “LocID”. With help from this article, first we create a view to get 3D coordinates (6378 = Earth’s [...]

Given a column of polar directions in degrees, this is a single SQL expression to compute their average, for use in a GROUP BY query. Some functions may be MySQL-specific.
IF(DEGREES(ATAN2(
-AVG(SIN(RADIANS(direction_deg)))
,-AVG(COS(RADIANS(direction_deg))))
) < 180
[...]