MySQL: disable server-side filtering when SRS is geographic with MySQ…

…L >= 8 (fixes qgis/QGIS#55463)

It seems spatial predicates are totally broken when using geographic SRS. For some reason

select MBRIntersects(ST_GeomFromText('POLYGON((-90 -90, 90 -90, 90 90, -90 90, -90 -90))', 4326), ST_GeomFromText('POINT(0 0)', 4326));

returns true as expected

But

select MBRIntersects(ST_GeomFromText('POLYGON((-179 -89, 179 -89, 179 89, -179 89, -179 -89))', 4326, 'axis-order=long-lat'), ST_GeomFromText('POINT(0 0)', 4326));

returns false !!!!

And

select MBRIntersects(ST_GeomFromText('POLYGON((-179 -89, 179 -89, 179 89, -179 89, -179 -89))', 32631), ST_GeomFromText('POINT(0 0)', 32631));

returns true as expected

Consequence, it seems safer to disable spatial filtering on layers with geographic coordinates with MySQL...

autotest/ogr/ogr_mysql.py

@@ -960,6 +960,11 @@ def test_ogr_mysql_longlat(mysql_ds, mysql_is_8_or_later):
             pytest.fail("Not found SRID definition with GEOMETORY field.")
         mysql_ds.ReleaseResultSet(sql_lyr)
 
+    lyr.SetSpatialFilterRect(-181, -91, 181, 91)
+    lyr.ResetReading()
+    f = lyr.GetNextFeature()
+    ogrtest.check_feature_geometry(f, geom)
+
 
 ###############################################################################
 # Test writing and reading back geometries

ogr/ogrsf_frmts/mysql/ogr_mysql.h

@@ -152,6 +152,8 @@ class OGRMySQLLayer CPL_NON_FINAL : public OGRLayer
     /* custom methods */
     virtual OGRFeature *RecordToFeature(char **papszRow, unsigned long *);
     virtual OGRFeature *GetNextRawFeature();
+
+    bool HasWorkingSpatialFilter();
 };
 
 /************************************************************************/

ogr/ogrsf_frmts/mysql/ogrmysqllayer.cpp

@@ -373,3 +373,18 @@ const OGRSpatialReference *OGRMySQLGeomFieldDefn::GetSpatialRef() const
 
     return poSRS;
 }
+
+/************************************************************************/
+/*                          HasWorkingSpatialFilter()                   */
+/************************************************************************/
+
+bool OGRMySQLLayer::HasWorkingSpatialFilter()
+{
+    if (poDS->GetMajorVersion() < 8 || poDS->IsMariaDB())
+        return true;
+    auto l_poSRS = GetSpatialRef();
+    // Spatial filtering with geographic SRS with MySQL >= 8 is too unreliable.
+    // Cf the following which returns 0...
+    // SELECT MBRIntersects(ST_GeomFromText('POLYGON((-179 -89, 179 -89, 179 89, -179 89, -179 -89))', 4326, 'axis-order=long-lat'), ST_GeomFromText('POINT(0 0)', 4326));
+    return !l_poSRS || !l_poSRS->IsGeographic();
+}

ogr/ogrsf_frmts/mysql/ogrmysqltablelayer.cpp

@@ -32,6 +32,8 @@
 #include "cpl_string.h"
 #include "ogr_mysql.h"
 
+#include <algorithm>
+
 /************************************************************************/
 /*                         OGRMySQLTableLayer()                         */
 /************************************************************************/
@@ -458,7 +460,7 @@ void OGRMySQLTableLayer::BuildWhere()
     pszWHERE = (char *)CPLMalloc(nWHERELen);
     pszWHERE[0] = '\0';
 
-    if (m_poFilterGeom != nullptr && pszGeomColumn)
+    if (m_poFilterGeom != nullptr && pszGeomColumn && HasWorkingSpatialFilter())
     {
         char szEnvelope[400];
         OGREnvelope sEnvelope;
@@ -467,22 +469,34 @@ void OGRMySQLTableLayer::BuildWhere()
         // POLYGON((MINX MINY, MAXX MINY, MAXX MAXY, MINX MAXY, MINX MINY))
         m_poFilterGeom->getEnvelope(&sEnvelope);
 
+        const OGRSpatialReference *l_poSRS = GetSpatialRef();
+        const bool bNeedAxisOrder =
+            (poDS->GetMajorVersion() >= 8 && !poDS->IsMariaDB() && l_poSRS &&
+             l_poSRS->IsGeographic());
+
+        double dfMinX = sEnvelope.MinX;
+        double dfMinY = sEnvelope.MinY;
+        double dfMaxX = sEnvelope.MaxX;
+        double dfMaxY = sEnvelope.MaxY;
+        if (bNeedAxisOrder)
+        {
+            // MySQL is super restrictive on coordinate ranges for filter with
+            // geographic coordinates...
+            constexpr double EPS = 1e-5;
+            dfMinX = std::max(-180.0 + EPS, dfMinX);
+            dfMinY = std::max(-90.0 + EPS, dfMinY);
+            dfMaxX = std::min(180.0 - EPS, dfMaxX);
+            dfMaxY = std::min(90.0 - EPS, dfMaxY);
+        }
+
         CPLsnprintf(szEnvelope, sizeof(szEnvelope),
                     "POLYGON((%.18g %.18g, %.18g %.18g, %.18g %.18g, %.18g "
                     "%.18g, %.18g %.18g))",
-                    sEnvelope.MinX, sEnvelope.MinY, sEnvelope.MaxX,
-                    sEnvelope.MinY, sEnvelope.MaxX, sEnvelope.MaxY,
-                    sEnvelope.MinX, sEnvelope.MaxY, sEnvelope.MinX,
-                    sEnvelope.MinY);
-
-        const char *pszAxisOrder = "";
-        OGRSpatialReference *l_poSRS = GetSpatialRef();
-        if (poDS->GetMajorVersion() >= 8 && !poDS->IsMariaDB() && l_poSRS &&
-            l_poSRS->IsGeographic())
-        {
-            pszAxisOrder = ", 'axis-order=long-lat'";
-        }
+                    dfMinX, dfMinY, dfMaxX, dfMinY, dfMaxX, dfMaxY, dfMinX,
+                    dfMaxY, dfMinX, dfMinY);
 
+        const char *pszAxisOrder =
+            bNeedAxisOrder ? ", 'axis-order=long-lat'" : "";
         snprintf(
             pszWHERE, nWHERELen, "WHERE MBRIntersects(%s('%s', %d%s), `%s`)",
             poDS->GetMajorVersion() >= 8 ? "ST_GeomFromText" : "GeomFromText",
@@ -497,6 +511,9 @@ void OGRMySQLTableLayer::BuildWhere()
             snprintf(pszWHERE + strlen(pszWHERE), nWHERELen - strlen(pszWHERE),
                      "&& (%s) ", pszQuery);
     }
+
+    if (pszWHERE[0])
+        CPLDebug("MYSQL", "Filter: %s", pszWHERE);
 }
 
 /************************************************************************/
@@ -634,7 +651,7 @@ int OGRMySQLTableLayer::TestCapability(const char *pszCap)
         return TRUE;
 
     else if (EQUAL(pszCap, OLCFastSpatialFilter))
-        return TRUE;
+        return HasWorkingSpatialFilter();
 
     else if (EQUAL(pszCap, OLCFastGetExtent))
         return TRUE;