[mapserver-users] Connect Mapserver to datawarehouse via ODBC(?) driver

[Никита Щипков]

Hello everyone!

I'm researching possibilities to connect a datawarehouse (Clickhouse) to
Mapserver. It was chosen for its query execution performance and
its capability of supporting geographic data types (Points, Rings and
(Multi-)Polygons).

My current questions are:
- What are the most potential capabilities of Mapserver to establish and
test a connection with Clickhouse (ODBC, e.g.)? More info here: Introduction
| ClickHouse Documentation <https://clickhouse.com/docs/en/interfaces/>

- Clickhouse works with a slightly different SQL dialect and methods of
converting geo types into each other than PostGIS. E.g. a Point in CH is
basically a Tuple containing two Float values, and a Ring (polygon without
holes) is an Array of Tuples (Geo | ClickHouse Documentation
<https://clickhouse.com/docs/en/sql-reference/data-types/geo/>). What are
the chances that Mapserver would adequately parse the following query and
related CH Geotypes?

select
Cast(toString(arrayZip(groupArray(ptr.x), groupArray(ptr.y))), 'Ring') as
geom
from default.points_to_ring ptr;


Feel free to ask any questions.
Thank you!
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