I am using QGIS 3.16.

I computed an Origin Destination Matrix for my studies using a total of 2478 (x13) routes. I then computed an SQL query in order to match each start point with its nearest end point. But this only computed 2458 routes (when it should have computed 2478).

Does anyone know why this is the case or what may have happened?

My SQL input is below. The algorhitm's ran smoothly and no error messages appeared, so I'm not quite sure why it cut layers out.

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  • 2
    It is always good to provide as much information as you can. In your case it would be helpful to see your SQL statement and even the tablestructure. – eurojam Feb 11 at 11:47
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    Are there any origin-destination relations that routing has not been successful for (eg NULL values in the total_cost column)? – root676 Feb 11 at 15:50
  • Unfortunately not, all the relations have attributes and the OD matrix itself accounted for all the possible routes (2478x13). I am at a loss. – Conor O'Driscoll Feb 12 at 12:13

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