I've recently implemented a revised geodatabase in Native SQL Server that is drawn upon in ArcGIS through a Server Query Layer. It works well for showing near real time satellite data locations for individuals in the field, however, when I wanted to convert points feature to a line, the tool in ArcGIS failed.
Upon analysis, the problem was the name for the SHAPE field. In the SQL tables and Query Layer the Geometry field was called GeoPOINT and it needed to be called SHAPE. This seems obvious now, but when some tools work and some don't we don't always suspect the most likely candidate.
Solution:
The easy solution was to rename GeoPOINT to SHAPE in the query layer as modifying the schema in SQL server is more difficult.
Other Interesting Facts Uncovered:
(1) Exporting the data from the query layer to a shape field removes the time field from a date/time field.
(2) Exporting the data from the query layer to a file geodatabase kept the GeoPOINT column as the default SHAPE and still could not be used for the points-to-line tool.
Tool Development Tips: (when coding in python)
(1) known-check for column name of the identification field (FID, OID, OBJECTID) for feature classes
(2) new-check for the column name for the SHAPE. It may not be SHAPE! for feature classes