MapInfo Pro

Hello, I have two polygons layers (see image below, an easy example): a blue polygons layer (rectangles) and a yellow polygons layer (triangles and circles).

My goal is to select objects of yellow layer intersected by blue layer: the circle.
The problem is the boundary!!

Using "intersects" operator in SQL Select MIPRO selects also triangles, in other words it selects also yellow objects having only the border/boundary in common with blue layer. I want a "real" intersection, not only the boundaries.

What could be a good solution?

I tried to use negative buffers without success.

I tried to use the overlap function but it is difficult to distinguish a real intersection from a boundary intersection with only the measure of the overlapping area.

Thanks in advance.

Michele

Hi Michelle,

one easy option can be calculating the area of ovelap and selecing non zeroes,

This is mapbasic code

Add Column "YELLOWLAYER" (SumOfIntersectingArea Float) From BLUELAYER Set To proportion sum(Area(obj, "sq m")) Where intersects Dynamic

You can do it from Table - Update Column

1.Table to Update: YELLOWLAYER

2.Get Value From Table : BLUELAYER

       > Join: choose İntersects

3.Column To Update: Add New Temporary column

4. Calculate: Proportion Sum

5. of : choose  Expression  and select Area  from Function list     

And the result will like

Then you can query the objects with PropSumOfArea > 0 will give you  overlapping ones, not the touching ones.

......

MapInfo should have several options like this in the functions

Intersects : Both touches and overlaps

Touches: not overlap but intersects

Overlaps: intersects with overlapping area >0

------------------------------
Ahmet Dabanli
Başarsoft
Balgat, Cankaya

Original Message:
Sent: 07-04-2023 14:53
From: Michele Burgalossi
Subject: SQL Select - Select polygons intersection without boundary intersections

Hello, I have two polygons layers (see image below, an easy example): a blue polygons layer (rectangles) and a yellow polygons layer (triangles and circles).

My goal is to select objects of yellow layer intersected by blue layer: the circle.
The problem is the boundary!!

Using "intersects" operator in SQL Select MIPRO selects also triangles, in other words it selects also yellow objects having only the border/boundary in common with blue layer. I want a "real" intersection, not only the boundaries.

What could be a good solution?

I tried to use negative buffers without success.

I tried to use the overlap function but it is difficult to distinguish a real intersection from a boundary intersection with only the measure of the overlapping area.

Thanks in advance.

Michele