MapD Charting Will Only Render Exactly 10 Million Geographic Coordinates After Table Size Exceeds Threshold


And for your question regarding:

SELECT count FROM table_name WHERE (device_lon >= -179.9999999999995 AND device_lon <= 179.99999999999898) AND (device_lat >= -1.2078378628389714 AND device_lat <= 53.84876223007643) LIMIT 10000001

I found something very weird. The above query returned a higher number versus doing a select count(*) on the entire table. I don’t have the 90 M table anymore, but I tried it on a table with 1 B rows.

The simple SELECT COUNT() without any filters returns: 1073708701
) with the filters returns: 1070310172

Why would that be the case?



Please examine and share the mapd_server.INFO file where you had the failure on the COPY FROM. My suspicion is that you have a Dictionary encoded TEXT column that has unique values being stored in it.
There is a limit of 1B unique Dictionary Encoded String. Please change any unique TEXT column to use TEXT ENCODING NONE.

Your second question, it appear that the value for the unfiltered 1073708701 is larger than the filtered query 1070310172, this seems normal.