diff --git a/python/plugins/processing/algs/gdal/Buffer.py b/python/plugins/processing/algs/gdal/Buffer.py
index d21db4f78e7..3b1428bb962 100644
--- a/python/plugins/processing/algs/gdal/Buffer.py
+++ b/python/plugins/processing/algs/gdal/Buffer.py
@@ -116,6 +116,11 @@ class Buffer(GdalAlgorithm):
                 continue
             other_fields.append(f.name())
 
+        if other_fields:
+            other_fields = ', {}'.format(','.join(other_fields))
+        else:
+            other_fields = ''
+
         arguments = []
         arguments.append(output)
         arguments.append(ogrLayer)
@@ -124,9 +129,9 @@ class Buffer(GdalAlgorithm):
         arguments.append('-sql')
 
         if dissolve or fieldName:
-            sql = "SELECT ST_Union(ST_Buffer({}, {})) AS {}, {} FROM '{}'".format(geometry, distance, geometry, ','.join(other_fields), layerName)
+            sql = "SELECT ST_Union(ST_Buffer({}, {})) AS {}{} FROM '{}'".format(geometry, distance, geometry, other_fields, layerName)
         else:
-            sql = "SELECT ST_Buffer({}, {}) AS {}, {} FROM '{}'".format(geometry, distance, geometry, ','.join(other_fields), layerName)
+            sql = "SELECT ST_Buffer({}, {}) AS {}{} FROM '{}'".format(geometry, distance, geometry, other_fields, layerName)
 
         if fieldName:
             sql = '{} GROUP BY {}'.format(sql, fieldName)
diff --git a/python/plugins/processing/algs/gdal/Dissolve.py b/python/plugins/processing/algs/gdal/Dissolve.py
index 5642b1ecb90..b523a31beff 100644
--- a/python/plugins/processing/algs/gdal/Dissolve.py
+++ b/python/plugins/processing/algs/gdal/Dissolve.py
@@ -127,6 +127,11 @@ class Dissolve(GdalAlgorithm):
 
             other_fields.append(f.name())
 
+        if other_fields:
+            other_fields = ', {}'.format(','.join(other_fields))
+        else:
+            other_fields = ''
+
         arguments = []
         arguments.append(output)
         arguments.append(ogrLayer)
@@ -148,12 +153,12 @@ class Dissolve(GdalAlgorithm):
         params = ','.join(tokens)
         if params:
             if self.parameterAsBool(parameters, self.KEEP_ATTRIBUTES, context):
-                sql = "SELECT ST_Union({}) AS {}, {}, {} FROM {} GROUP BY {}".format(geometry, geometry, ','.join(other_fields), params, layerName, fieldName)
+                sql = "SELECT ST_Union({}) AS {}{}, {} FROM {} GROUP BY {}".format(geometry, geometry, other_fields, params, layerName, fieldName)
             else:
                 sql = "SELECT ST_Union({}) AS {}, {}, {} FROM {} GROUP BY {}".format(geometry, geometry, fieldName, params, layerName, fieldName)
         else:
             if self.parameterAsBool(parameters, self.KEEP_ATTRIBUTES, context):
-                sql = "SELECT ST_Union({}) AS {}, {} FROM {} GROUP BY {}".format(geometry, geometry, ','.join(other_fields), layerName, fieldName)
+                sql = "SELECT ST_Union({}) AS {}{} FROM {} GROUP BY {}".format(geometry, geometry, other_fields, layerName, fieldName)
             else:
                 sql = "SELECT ST_Union({}) AS {}, {} FROM {} GROUP BY {}".format(geometry, geometry, fieldName, layerName, fieldName)
 
diff --git a/python/plugins/processing/algs/gdal/OffsetCurve.py b/python/plugins/processing/algs/gdal/OffsetCurve.py
index 07890e1fab8..d86972596b4 100644
--- a/python/plugins/processing/algs/gdal/OffsetCurve.py
+++ b/python/plugins/processing/algs/gdal/OffsetCurve.py
@@ -97,6 +97,11 @@ class OffsetCurve(GdalAlgorithm):
                 continue
             other_fields.append(f.name())
 
+        if other_fields:
+            other_fields = ', {}'.format(','.join(other_fields))
+        else:
+            other_fields = ''
+
         arguments = []
         arguments.append(output)
         arguments.append(ogrLayer)
@@ -104,7 +109,7 @@ class OffsetCurve(GdalAlgorithm):
         arguments.append('sqlite')
         arguments.append('-sql')
 
-        sql = "SELECT ST_OffsetCurve({}, {}) AS {}, {} FROM '{}'".format(geometry, distance, geometry, ','.join(other_fields), layerName)
+        sql = "SELECT ST_OffsetCurve({}, {}) AS {}{} FROM '{}'".format(geometry, distance, geometry, other_fields, layerName)
         arguments.append(sql)
 
         if options:
diff --git a/python/plugins/processing/algs/gdal/OneSideBuffer.py b/python/plugins/processing/algs/gdal/OneSideBuffer.py
index 2d781cbb548..27913355558 100644
--- a/python/plugins/processing/algs/gdal/OneSideBuffer.py
+++ b/python/plugins/processing/algs/gdal/OneSideBuffer.py
@@ -126,6 +126,11 @@ class OneSideBuffer(GdalAlgorithm):
                 continue
             other_fields.append(f.name())
 
+        if other_fields:
+            other_fields = ', {}'.format(','.join(other_fields))
+        else:
+            other_fields = ''
+
         arguments = []
         arguments.append(output)
         arguments.append(ogrLayer)
@@ -134,9 +139,9 @@ class OneSideBuffer(GdalAlgorithm):
         arguments.append('-sql')
 
         if dissolve or fieldName:
-            sql = "SELECT ST_Union(ST_SingleSidedBuffer({}, {}, {})) AS {}, {} FROM '{}'".format(geometry, distance, side, geometry, ','.join(other_fields), layerName)
+            sql = "SELECT ST_Union(ST_SingleSidedBuffer({}, {}, {})) AS {}{} FROM '{}'".format(geometry, distance, side, geometry, other_fields, layerName)
         else:
-            sql = "SELECT ST_SingleSidedBuffer({}, {}, {}) AS {}, {} FROM '{}'".format(geometry, distance, side, geometry, ','.join(other_fields), layerName)
+            sql = "SELECT ST_SingleSidedBuffer({}, {}, {}) AS {}{} FROM '{}'".format(geometry, distance, side, geometry, other_fields, layerName)
 
         if fieldName:
             sql = '"{} GROUP BY {}"'.format(sql, fieldName)
diff --git a/python/plugins/processing/algs/gdal/PointsAlongLines.py b/python/plugins/processing/algs/gdal/PointsAlongLines.py
index 3af72072ef1..95362ad17ce 100644
--- a/python/plugins/processing/algs/gdal/PointsAlongLines.py
+++ b/python/plugins/processing/algs/gdal/PointsAlongLines.py
@@ -102,6 +102,11 @@ class PointsAlongLines(GdalAlgorithm):
                 continue
             other_fields.append(f.name())
 
+        if other_fields:
+            other_fields = ', {}'.format(','.join(other_fields))
+        else:
+            other_fields = ''
+
         arguments = []
         arguments.append(output)
         arguments.append(ogrLayer)
@@ -109,7 +114,7 @@ class PointsAlongLines(GdalAlgorithm):
         arguments.append('sqlite')
         arguments.append('-sql')
 
-        sql = "SELECT ST_Line_Interpolate_Point({}, {}) AS {}, {} FROM '{}'".format(geometry, distance, geometry, ','.join(other_fields), layerName)
+        sql = "SELECT ST_Line_Interpolate_Point({}, {}) AS {}{} FROM '{}'".format(geometry, distance, geometry, other_fields, layerName)
         arguments.append(sql)
 
         if options: