Reload data when subsetString changes.

src/providers/delimitedtext/qgsdelimitedtextprovider.cpp

@@ -1081,6 +1081,7 @@ bool QgsDelimitedTextProvider::setSubsetString( QString subset, bool updateFeatu
     }
   }
 
+  emit dataChanged();
   return valid;
 }
 

src/providers/memory/qgsmemoryprovider.cpp

@@ -443,6 +443,8 @@ bool QgsMemoryProvider::setSubsetString( QString theSQL, bool updateFeatureCount
   }
 
   mSubsetString = theSQL;
+
+  emit dataChanged();
   return true;
 }
 

src/providers/mssql/qgsmssqlprovider.cpp

@@ -1426,6 +1426,8 @@ bool QgsMssqlProvider::setSubsetString( QString theSQL, bool )
 
   mExtent.setMinimal();
 
+  emit dataChanged();
+
   return true;
 }
 

src/providers/ogr/qgsogrprovider.cpp

@@ -556,6 +556,8 @@ bool QgsOgrProvider::setSubsetString( QString theSQL, bool updateFeatureCount )
     extent_ = 0;
   }
 
+  emit dataChanged();
+
   return true;
 }
 

src/providers/oracle/qgsoracleprovider.cpp

@@ -1978,6 +1978,8 @@ bool QgsOracleProvider::setSubsetString( QString theSQL, bool updateFeatureCount
   }
   mLayerExtent.setMinimal();
 
+  emit dataChanged();
+
   return true;
 }
 

src/providers/postgres/qgspostgresprovider.cpp

@@ -2488,6 +2488,8 @@ bool QgsPostgresProvider::setSubsetString( QString theSQL, bool updateFeatureCou
   }
   mLayerExtent.setMinimal();
 
+  emit dataChanged();
+
   return true;
 }
 

src/providers/spatialite/qgsspatialiteprovider.cpp

@@ -3191,6 +3191,8 @@ bool QgsSpatiaLiteProvider::setSubsetString( QString theSQL, bool updateFeatureC
 
   getTableSummary();
 
+  emit dataChanged();
+
   return false;
 }