Decresead verbosity (closes #137).

diff --git a/src/gdaex.c b/src/gdaex.c
index 16515f56b5787379741b74ede2269e7fd99d1e7f..c30bbf1586440d5fb147bab6120f8e6d27e705ab 100644 (file)
--- a/src/gdaex.c
+++ b/src/gdaex.c
@@ -682,10 +682,6 @@ gchar
        if (col >= 0)
                {
                        value = gdaex_data_model_get_value_stringify_at (data_model, row, col);
-                       if (value == NULL)
-                               {
-                                       g_warning ("Error retrieving «%s»'s value.", field_name);
-                               }
                }
        else
                {
@@ -837,10 +833,6 @@ GdaTimestamp
        if (col >= 0)
                {
                        value = gdaex_data_model_get_value_gdatimestamp_at (data_model, row, col);
-                       if (value == NULL)
-                               {
-                                       g_warning ("Error retrieving «%s»'s value.", field_name);
-                               }
                }
        else
                {
@@ -848,7 +840,7 @@ GdaTimestamp
                        value = NULL;
                }
 
-       return gda_timestamp_copy ((gpointer)value);
+       return (GdaTimestamp *)gda_timestamp_copy ((gpointer)value);
 }
 
 /**
@@ -872,10 +864,6 @@ GDate
        if (col >= 0)
                {
                        value = gdaex_data_model_get_value_gdate_at (data_model, row, col);
-                       if (value == NULL)
-                               {
-                                       g_warning ("Error retrieving «%s»'s value.", field_name);
-                               }
                }
        else
                {
@@ -907,10 +895,6 @@ GDateTime
        if (col >= 0)
                {
                        value = gdaex_data_model_get_value_gdatetime_at (data_model, row, col);
-                       if (value == NULL)
-                               {
-                                       g_warning ("Error retrieving «%s»'s value.", field_name);
-                               }
                }
        else
                {
@@ -942,10 +926,6 @@ struct tm
        if (col >= 0)
                {
                        value = gdaex_data_model_get_value_tm_at (data_model, row, col);
-                       if (value == NULL)
-                               {
-                                       g_warning ("Error retrieving «%s»'s value.", field_name);
-                               }
                }
        else
                {
@@ -974,7 +954,7 @@ gchar
        error = NULL;
 
        v = gda_data_model_get_value_at (data_model, col, row, &error);
-       if (error == NULL)
+       if (v != NULL && error == NULL)
                {
                        if (!gda_value_is_null (v))
                                {
@@ -987,7 +967,8 @@ gchar
                }
        else
                {
-                       g_warning ("Error on retrieving field's value: %s\n",
+                       g_warning ("Error on retrieving field's value: «%s».\n%s\n",
+                                  gda_data_model_get_column_name (data_model, col),
                                   error->message != NULL ? error->message : "no details");
                        ret = NULL;
                }
@@ -1013,12 +994,7 @@ gdaex_data_model_get_value_integer_at (GdaDataModel *data_model, gint row, gint
        error = NULL;
 
        v = gda_data_model_get_value_at (data_model, col, row, &error);
-       if (error != NULL)
-               {
-                       g_warning ("Error on retrieving field's value: %s\n",
-                                  error->message != NULL ? error->message : "no details");
-               }
-       else
+       if (v != NULL && error == NULL)
                {
                        if (gda_value_isa (v, G_TYPE_INT))
                                {
@@ -1029,6 +1005,12 @@ gdaex_data_model_get_value_integer_at (GdaDataModel *data_model, gint row, gint
                                        ret = strtol (gda_value_stringify (v), NULL, 10);
                                }
                }
+       else
+               {
+                       g_warning ("Error on retrieving field's value: «%s».\n%s\n",
+                                  gda_data_model_get_column_name (data_model, col),
+                                  error->message != NULL ? error->message : "no details");
+               }
 
        return ret;
 }
@@ -1051,12 +1033,7 @@ gdaex_data_model_get_value_float_at (GdaDataModel *data_model, gint row, gint co
        error = NULL;
 
        v = gda_data_model_get_value_at (data_model, col, row, &error);
-       if (error != NULL)
-               {
-                       g_warning ("Error on retrieving field's value: %s\n",
-                                  error->message != NULL ? error->message : "no details");
-               }
-       else
+       if (v != NULL && error == NULL)
                {
                        if (gda_value_isa (v, G_TYPE_FLOAT))
                                {
@@ -1067,6 +1044,12 @@ gdaex_data_model_get_value_float_at (GdaDataModel *data_model, gint row, gint co
                                        ret = g_strtod (gda_value_stringify (v), NULL);
                                }
                }
+       else
+               {
+                       g_warning ("Error on retrieving field's value: «%s».\n%s\n",
+                                  gda_data_model_get_column_name (data_model, col),
+                                  error->message != NULL ? error->message : "no details");
+               }
 
        return ret;
 }
@@ -1089,12 +1072,7 @@ gdaex_data_model_get_value_double_at (GdaDataModel *data_model, gint row, gint c
        error = NULL;
 
        v = gda_data_model_get_value_at (data_model, col, row, &error);
-       if (error != NULL)
-               {
-                       g_warning ("Error on retrieving field's value: %s\n",
-                                  error->message != NULL ? error->message : "no details");
-               }
-       else
+       if (v != NULL && error == NULL)
                {
                        if (gda_value_isa (v, G_TYPE_DOUBLE))
                                {
@@ -1105,6 +1083,12 @@ gdaex_data_model_get_value_double_at (GdaDataModel *data_model, gint row, gint c
                                        ret = g_strtod (gda_value_stringify (v), NULL);
                                }
                }
+       else
+               {
+                       g_warning ("Error on retrieving field's value: «%s».\n%s\n",
+                                  gda_data_model_get_column_name (data_model, col),
+                                  error->message != NULL ? error->message : "no details");
+               }
 
        return ret;
 }
@@ -1127,12 +1111,7 @@ gdaex_data_model_get_value_boolean_at (GdaDataModel *data_model, gint row, gint
        error = NULL;
 
        v = gda_data_model_get_value_at (data_model, col, row, &error);
-       if (error != NULL)
-               {
-                       g_warning ("Error on retrieving field's value: %s\n",
-                                  error->message != NULL ? error->message : "no details");
-               }
-       else
+       if (v != NULL && error == NULL)
                {
                        if (gda_value_isa (v, G_TYPE_BOOLEAN))
                                {
@@ -1140,7 +1119,7 @@ gdaex_data_model_get_value_boolean_at (GdaDataModel *data_model, gint row, gint
                                }
                        else
                                {
-                                       gchar *vstr = g_strstrip (gda_value_stringify (v));
+                                       gchar *vstr = g_strstrip (g_strdup (gda_value_stringify (v)));
                                        if (strcasecmp (vstr, "true") == 0 ||
                                                strcasecmp (vstr, "t") == 0 ||
                                                strcasecmp (vstr, "yes") == 0 ||
@@ -1153,8 +1132,15 @@ gdaex_data_model_get_value_boolean_at (GdaDataModel *data_model, gint row, gint
                                                {
                                                        ret = FALSE;
                                                }
+                                       g_free (vstr);
                                }
                }
+       else
+               {
+                       g_warning ("Error on retrieving field's value: «%s».\n%s\n",
+                                  gda_data_model_get_column_name (data_model, col),
+                                  error->message != NULL ? error->message : "no details");
+               }
 
        return ret;
 }
@@ -1178,71 +1164,77 @@ GdaTimestamp
        error = NULL;
 
        v = gda_data_model_get_value_at (data_model, col, row, &error);
-       if (v == NULL || error != NULL)
+       if (v != NULL && error == NULL)
                {
-                       g_warning ("Error on retrieving field's value: %s\n",
-                                  error->message != NULL ? error->message : "no details");
-               }
-       else if (!gda_value_is_null (v))
-               {
-                       if (gda_value_isa (v, GDA_TYPE_TIMESTAMP))
-                               {
-                                       gdatimestamp = (GdaTimestamp *)gda_value_get_timestamp (v);
-                               }
-                       else if (gda_value_isa (v, G_TYPE_DATE_TIME))
+                       if (!gda_value_is_null (v))
                                {
-                                       GDateTime *gdatetime;
+                                       if (gda_value_isa (v, GDA_TYPE_TIMESTAMP))
+                                               {
+                                                       gdatimestamp = (GdaTimestamp *)gda_value_get_timestamp (v);
+                                               }
+                                       else if (gda_value_isa (v, G_TYPE_DATE_TIME))
+                                               {
+                                                       GDateTime *gdatetime;
                                        
-                                       gdatetime = gdaex_data_model_get_value_gdatetime_at (data_model, row, col);
-                                       gdatimestamp = g_malloc0 (sizeof (GdaTimestamp));
-                                       gdatimestamp->year = g_date_time_get_year (gdatetime);
-                                       gdatimestamp->month = g_date_time_get_month (gdatetime);
-                                       gdatimestamp->day = g_date_time_get_day_of_month (gdatetime);
-                                       gdatimestamp->hour = g_date_time_get_hour (gdatetime);
-                                       gdatimestamp->minute = g_date_time_get_minute (gdatetime);
-                                       gdatimestamp->second = g_date_time_get_second (gdatetime);
-                               }
-                       else if (gda_value_isa (v, G_TYPE_DATE))
-                               {
-                                       GDate *date;
+                                                       gdatetime = gdaex_data_model_get_value_gdatetime_at (data_model, row, col);
+                                                       gdatimestamp = g_malloc0 (sizeof (GdaTimestamp));
+                                                       gdatimestamp->year = g_date_time_get_year (gdatetime);
+                                                       gdatimestamp->month = g_date_time_get_month (gdatetime);
+                                                       gdatimestamp->day = g_date_time_get_day_of_month (gdatetime);
+                                                       gdatimestamp->hour = g_date_time_get_hour (gdatetime);
+                                                       gdatimestamp->minute = g_date_time_get_minute (gdatetime);
+                                                       gdatimestamp->second = g_date_time_get_second (gdatetime);
+                                               }
+                                       else if (gda_value_isa (v, G_TYPE_DATE))
+                                               {
+                                                       GDate *date;
 
-                                       date = gdaex_data_model_get_value_gdate_at (data_model, row, col);
+                                                       date = gdaex_data_model_get_value_gdate_at (data_model, row, col);
 
-                                       if (date != NULL)
-                                               {
-                                                       gdatimestamp = g_malloc0 (sizeof (GdaTimestamp));
-                                                       if (g_date_valid (date))
+                                                       if (date != NULL)
                                                                {
-                                                                       gdatimestamp->year = g_date_get_year (date);
-                                                                       gdatimestamp->month = g_date_get_month (date);
-                                                                       gdatimestamp->day = g_date_get_day (date);
-                                                               }
-                                                       else
-                                                               {
-                                                                       gdatimestamp->year = date->year;
-                                                                       gdatimestamp->month = date->month;
-                                                                       gdatimestamp->day = date->day;
+                                                                       gdatimestamp = g_new0 (GdaTimestamp, 1);
+                                                                       if (g_date_valid (date))
+                                                                               {
+                                                                                       gdatimestamp->year = g_date_get_year (date);
+                                                                                       gdatimestamp->month = g_date_get_month (date);
+                                                                                       gdatimestamp->day = g_date_get_day (date);
+                                                                               }
+                                                                       else
+                                                                               {
+                                                                                       gdatimestamp->year = date->year;
+                                                                                       gdatimestamp->month = date->month;
+                                                                                       gdatimestamp->day = date->day;
+                                                                               }
+                                                                       g_date_free (date);
                                                                }
                                                }
-                               }
-                       else if (gda_value_isa (v, GDA_TYPE_TIME))
-                               {
-                                       const GdaTime *time;
+                                       else if (gda_value_isa (v, GDA_TYPE_TIME))
+                                               {
+                                                       const GdaTime *time;
 
-                                       time = gda_value_get_time (v);
+                                                       time = gda_value_get_time (v);
 
-                                       if (time != NULL)
+                                                       if (time != NULL)
+                                                               {
+                                                                       gdatimestamp = g_new0 (GdaTimestamp, 1);
+                                                                       gdatimestamp->hour = time->hour;
+                                                                       gdatimestamp->minute = time->minute;
+                                                                       gdatimestamp->second = time->second;
+                                                               }
+                                               }
+                                       else
                                                {
-                                                       gdatimestamp = g_malloc0 (sizeof (GdaTimestamp));
-                                                       gdatimestamp->hour = time->hour;
-                                                       gdatimestamp->minute = time->minute;
-                                                       gdatimestamp->second = time->second;
+                                                       g_warning ("Error on retrieving field's value: «%s».\nUnknown GValue type.",
+                                                                  gda_data_model_get_column_name (data_model, col));
                                                }
                                }
-                       else
-                               {
-                                       g_warning ("Error on retrieving field's value: unknown GValue type.");
-                               }
+               }
+       else
+               {
+                       g_warning ("Error on retrieving field's value: «%s».\n%s\n",
+                                  gda_data_model_get_column_name (data_model, col),
+                                  error->message != NULL ? error->message : "no details");
                }
 
        return (GdaTimestamp *)gda_timestamp_copy ((gpointer)gdatimestamp);
@@ -1269,36 +1261,41 @@ GDate
        error = NULL;
 
        v = gda_data_model_get_value_at (data_model, col, row, &error);
-       if (v == NULL || error != NULL)
+       if (v != NULL && error == NULL)
                {
-                       g_warning ("Error on retrieving field's value: %s\n",
-                                  error->message != NULL ? error->message : "no details");
-               }
-       else if (!gda_value_is_null (v))
-               {
-                       if (gda_value_isa (v, GDA_TYPE_TIMESTAMP))
-                               {
-                                       gdatimestamp = gdaex_data_model_get_value_gdatimestamp_at (data_model, row, col);
-                                       ret = g_date_new_dmy ((GDateYear)gdatimestamp->year,
-                                                             (GDateMonth)gdatimestamp->month,
-                                                             (GDateDay)gdatimestamp->day);
-                               }
-                       else if (gda_value_isa (v, G_TYPE_DATE_TIME))
-                               {
-                                       gdatetime = gdaex_data_model_get_value_gdatetime_at (data_model, row, col);
-                                       ret = g_date_new_dmy ((GDateYear)g_date_time_get_year ((GDateTime *)gdatetime),
-                                                             (GDateMonth)g_date_time_get_month ((GDateTime *)gdatetime),
-                                                             (GDateDay)g_date_time_get_day_of_month ((GDateTime *)gdatetime));
-                               }
-                       else if (gda_value_isa (v, G_TYPE_DATE))
-                               {
-                                       ret = (GDate *)g_value_get_boxed (v);
-                               }
-                       else
+                       if (!gda_value_is_null (v))
                                {
-                                       g_warning ("Error on retrieving field's value: unknown GValue type.");
+                                       if (gda_value_isa (v, GDA_TYPE_TIMESTAMP))
+                                               {
+                                                       gdatimestamp = gdaex_data_model_get_value_gdatimestamp_at (data_model, row, col);
+                                                       ret = g_date_new_dmy ((GDateYear)gdatimestamp->year,
+                                                                             (GDateMonth)gdatimestamp->month,
+                                                                             (GDateDay)gdatimestamp->day);
+                                               }
+                                       else if (gda_value_isa (v, G_TYPE_DATE_TIME))
+                                               {
+                                                       gdatetime = gdaex_data_model_get_value_gdatetime_at (data_model, row, col);
+                                                       ret = g_date_new_dmy ((GDateYear)g_date_time_get_year ((GDateTime *)gdatetime),
+                                                                             (GDateMonth)g_date_time_get_month ((GDateTime *)gdatetime),
+                                                                             (GDateDay)g_date_time_get_day_of_month ((GDateTime *)gdatetime));
+                                               }
+                                       else if (gda_value_isa (v, G_TYPE_DATE))
+                                               {
+                                                       ret = (GDate *)g_value_get_boxed (v);
+                                               }
+                                       else
+                                               {
+                                                       g_warning ("Error on retrieving field's value: «%s».\nUnknown GValue type.",
+                                                                  gda_data_model_get_column_name (data_model, col));
+                                               }
                                }
                }
+       else
+               {
+                       g_warning ("Error on retrieving field's value: «%s».\n%s\n",
+                                  gda_data_model_get_column_name (data_model, col),
+                                  error->message != NULL ? error->message : "no details");
+               }
 
        return ret;
 }
@@ -1324,42 +1321,47 @@ GDateTime
        error = NULL;
 
        v = gda_data_model_get_value_at (data_model, col, row, &error);
-       if (v == NULL || error != NULL)
-               {
-                       g_warning ("Error on retrieving field's value: %s\n",
-                                  error->message != NULL ? error->message : "no details");
-               }
-       else if (!gda_value_is_null (v))
+       if (v != NULL && error == NULL)
                {
-                       if (gda_value_isa (v, GDA_TYPE_TIMESTAMP))
-                               {
-                                       gdatimestamp = gdaex_data_model_get_value_gdatimestamp_at (data_model, row, col);
-                                       ret = g_date_time_new_local ((gint)gdatimestamp->year,
-                                                                    (gint)gdatimestamp->month,
-                                                                    (gint)gdatimestamp->day,
-                                                                    (gint)gdatimestamp->hour,
-                                                                    (gint)gdatimestamp->minute,
-                                                                    (gdouble)gdatimestamp->second);
-                               }
-                       else if (gda_value_isa (v, G_TYPE_DATE))
-                               {
-                                       gdate = gdaex_data_model_get_value_gdate_at (data_model, row, col);
-                                       ret = g_date_time_new_local ((gint)g_date_get_year (gdate),
-                                                                    (gint)g_date_get_month (gdate),
-                                                                    (gint)g_date_get_day (gdate),
-                                                                    0,
-                                                                    0,
-                                                                    0.0);
-                               }
-                       else if (gda_value_isa (v, G_TYPE_DATE_TIME))
-                               {
-                                       ret = (GDateTime *)g_value_get_boxed (v);
-                               }
-                       else
+                       if (!gda_value_is_null (v))
                                {
-                                       g_warning ("Error on retrieving field's value: unknown GValue type.");
+                                       if (gda_value_isa (v, GDA_TYPE_TIMESTAMP))
+                                               {
+                                                       gdatimestamp = gdaex_data_model_get_value_gdatimestamp_at (data_model, row, col);
+                                                       ret = g_date_time_new_local ((gint)gdatimestamp->year,
+                                                                                    (gint)gdatimestamp->month,
+                                                                                    (gint)gdatimestamp->day,
+                                                                                    (gint)gdatimestamp->hour,
+                                                                                    (gint)gdatimestamp->minute,
+                                                                                    (gdouble)gdatimestamp->second);
+                                               }
+                                       else if (gda_value_isa (v, G_TYPE_DATE))
+                                               {
+                                                       gdate = gdaex_data_model_get_value_gdate_at (data_model, row, col);
+                                                       ret = g_date_time_new_local ((gint)g_date_get_year (gdate),
+                                                                                    (gint)g_date_get_month (gdate),
+                                                                                    (gint)g_date_get_day (gdate),
+                                                                                    0,
+                                                                                    0,
+                                                                                    0.0);
+                                               }
+                                       else if (gda_value_isa (v, G_TYPE_DATE_TIME))
+                                               {
+                                                       ret = (GDateTime *)g_value_get_boxed (v);
+                                               }
+                                       else
+                                               {
+                                                       g_warning ("Error on retrieving field's value: «%s».\nUnknown GValue type.",
+                                                                  gda_data_model_get_column_name (data_model, col));
+                                               }
                                }
                }
+       else
+               {
+                       g_warning ("Error on retrieving field's value: «%s».\n%s\n",
+                                  gda_data_model_get_column_name (data_model, col),
+                                  error->message != NULL ? error->message : "no details");
+               }
 
        return ret;
 }
@@ -1383,29 +1385,33 @@ struct tm
        error = NULL;
 
        v = gda_data_model_get_value_at (data_model, col, row, &error);
-       if (v == NULL || error != NULL)
+       if (v != NULL && error == NULL)
                {
-                       g_warning ("Error on retrieving field's value: %s\n",
-                                  error->message != NULL ? error->message : "no details");
-               }
-       else if (!gda_value_is_null (v))
-               {
-                       GdaTimestamp *gdatimestamp;
-
-                       gdatimestamp = gdaex_data_model_get_value_gdatimestamp_at (data_model, row, col);
-
-                       if (gdatimestamp != NULL)
+                       if (!gda_value_is_null (v))
                                {
-                                       ret = g_malloc0 (sizeof (struct tm));
+                                       GdaTimestamp *gdatimestamp;
 
-                                       ret->tm_year = gdatimestamp->year - 1900;
-                                       ret->tm_mon = gdatimestamp->month - 1;
-                                       ret->tm_mday = gdatimestamp->day;
-                                       ret->tm_hour = gdatimestamp->hour;
-                                       ret->tm_min = gdatimestamp->minute;
-                                       ret->tm_sec = gdatimestamp->second;
+                                       gdatimestamp = gdaex_data_model_get_value_gdatimestamp_at (data_model, row, col);
+
+                                       if (gdatimestamp != NULL)
+                                               {
+                                                       ret = g_new0 (struct tm, 1);
+
+                                                       ret->tm_year = gdatimestamp->year - 1900;
+                                                       ret->tm_mon = gdatimestamp->month - 1;
+                                                       ret->tm_mday = gdatimestamp->day;
+                                                       ret->tm_hour = gdatimestamp->hour;
+                                                       ret->tm_min = gdatimestamp->minute;
+                                                       ret->tm_sec = gdatimestamp->second;
+                                               }
                                }
                }
+       else
+               {
+                       g_warning ("Error on retrieving field's value: «%s».\n%s\n",
+                                  gda_data_model_get_column_name (data_model, col),
+                                  error->message != NULL ? error->message : "no details");
+               }
 
        return ret;
 }
@@ -1419,7 +1425,7 @@ struct tm
  */
 gchar
 *gdaex_data_model_iter_get_field_value_stringify_at (GdaDataModelIter *iter,
-                                               const gchar *field_name)
+                                                     const gchar *field_name)
 {
        GdaDataModel *data_model;
        gchar *value;
@@ -1432,10 +1438,6 @@ gchar
        if (col >= 0)
                {
                        value = gdaex_data_model_iter_get_value_stringify_at (iter, col);
-                       if (value == NULL)
-                               {
-                                       g_warning ("Error retrieving «%s»'s value.", field_name);
-                               }
                }
        else
                {
@@ -1592,10 +1594,6 @@ GdaTimestamp
        if (col >= 0)
                {
                        value = gdaex_data_model_iter_get_value_gdatimestamp_at (iter, col);
-                       if (value == NULL)
-                               {
-                                       g_warning ("Error retrieving «%s»'s value.", field_name);
-                               }
                }
        else
                {
@@ -1603,7 +1601,7 @@ GdaTimestamp
                        value = NULL;
                }
 
-       return gda_timestamp_copy ((gpointer)value);
+       return (GdaTimestamp *)gda_timestamp_copy ((gpointer)value);
 }
 
 /**
@@ -1628,10 +1626,6 @@ GDate
        if (col >= 0)
                {
                        value = gdaex_data_model_iter_get_value_gdate_at (iter, col);
-                       if (value == NULL)
-                               {
-                                       g_warning ("Error retrieving «%s»'s value.", field_name);
-                               }
                }
        else
                {
@@ -1664,10 +1658,6 @@ GDateTime
        if (col >= 0)
                {
                        value = gdaex_data_model_iter_get_value_gdatetime_at (iter, col);
-                       if (value == NULL)
-                               {
-                                       g_warning ("Error retrieving «%s»'s value.", field_name);
-                               }
                }
        else
                {
@@ -1700,10 +1690,6 @@ struct tm
        if (col >= 0)
                {
                        value = gdaex_data_model_iter_get_value_tm_at (iter, col);
-                       if (value == NULL)
-                               {
-                                       g_warning ("Error retrieving «%s»'s value.", field_name);
-                               }
                }
        else
                {
@@ -1730,7 +1716,12 @@ gchar
        v = gda_data_model_iter_get_value_at (iter, col);
        if (v == NULL)
                {
-                       g_warning ("Error on retrieving field's value at column %d.", col);
+                       GdaDataModel *data_model;
+
+                       g_object_get (G_OBJECT (iter), "data-model", &data_model, NULL);
+
+                       g_warning ("Error on retrieving field's value: «%s».",
+                                  gda_data_model_get_column_name (data_model, col));
                }
        else
                {
@@ -1763,7 +1754,12 @@ gdaex_data_model_iter_get_value_integer_at (GdaDataModelIter *iter, gint col)
        v = gda_data_model_iter_get_value_at (iter, col);
        if (v == NULL)
                {
-                       g_warning ("Error on retrieving field's value at column %d.", col);
+                       GdaDataModel *data_model;
+
+                       g_object_get (G_OBJECT (iter), "data-model", &data_model, NULL);
+
+                       g_warning ("Error on retrieving field's value: «%s».",
+                                  gda_data_model_get_column_name (data_model, col));
                }
        else
                {
@@ -1796,7 +1792,12 @@ gdaex_data_model_iter_get_value_float_at (GdaDataModelIter *iter, gint col)
        v = gda_data_model_iter_get_value_at (iter, col);
        if (v == NULL)
                {
-                       g_warning ("Error on retrieving field's value at column %d.", col);
+                       GdaDataModel *data_model;
+
+                       g_object_get (G_OBJECT (iter), "data-model", &data_model, NULL);
+
+                       g_warning ("Error on retrieving field's value: «%s».",
+                                  gda_data_model_get_column_name (data_model, col));
                }
        else
                {
@@ -1829,7 +1830,12 @@ gdaex_data_model_iter_get_value_double_at (GdaDataModelIter *iter, gint col)
        v = gda_data_model_iter_get_value_at (iter, col);
        if (v == NULL)
                {
-                       g_warning ("Error on retrieving field's value at column %d.", col);
+                       GdaDataModel *data_model;
+
+                       g_object_get (G_OBJECT (iter), "data-model", &data_model, NULL);
+
+                       g_warning ("Error on retrieving field's value: «%s».",
+                                  gda_data_model_get_column_name (data_model, col));
                }
        else
                {
@@ -1862,7 +1868,12 @@ gdaex_data_model_iter_get_value_boolean_at (GdaDataModelIter *iter, gint col)
        v = gda_data_model_iter_get_value_at (iter, col);
        if (v == NULL)
                {
-                       g_warning ("Error on retrieving field's value at column %d.", col);
+                       GdaDataModel *data_model;
+
+                       g_object_get (G_OBJECT (iter), "data-model", &data_model, NULL);
+
+                       g_warning ("Error on retrieving field's value: «%s».",
+                                  gda_data_model_get_column_name (data_model, col));
                }
        else
                {
@@ -1872,7 +1883,7 @@ gdaex_data_model_iter_get_value_boolean_at (GdaDataModelIter *iter, gint col)
                                }
                        else
                                {
-                                       gchar *vstr = g_strstrip (gda_value_stringify (v));
+                                       gchar *vstr = g_strstrip (g_strdup (gda_value_stringify (v)));
                                        if (strcasecmp (vstr, "true") == 0 ||
                                                strcasecmp (vstr, "t") == 0 ||
                                                strcasecmp (vstr, "yes") == 0 ||
@@ -1885,6 +1896,7 @@ gdaex_data_model_iter_get_value_boolean_at (GdaDataModelIter *iter, gint col)
                                                {
                                                        ret = FALSE;
                                                }
+                                       g_free (vstr);
                                }
                }
 
@@ -1909,7 +1921,12 @@ GdaTimestamp
        v = gda_data_model_iter_get_value_at (iter, col);
        if (v == NULL)
                {
-                       g_warning ("Error on retrieving field's value at column %d.", col);
+                       GdaDataModel *data_model;
+
+                       g_object_get (G_OBJECT (iter), "data-model", &data_model, NULL);
+
+                       g_warning ("Error on retrieving field's value: «%s».",
+                                  gda_data_model_get_column_name (data_model, col));
                }
        else if (!gda_value_is_null (v))
                {
@@ -1938,7 +1955,7 @@ GdaTimestamp
 
                                        if (date != NULL)
                                                {
-                                                       gdatimestamp = g_malloc0 (sizeof (GdaTimestamp));
+                                                       gdatimestamp = g_new0 (GdaTimestamp, 1);
                                                        if (g_date_valid (date))
                                                                {
                                                                        gdatimestamp->year = g_date_get_year (date);
@@ -1951,6 +1968,7 @@ GdaTimestamp
                                                                        gdatimestamp->month = date->month;
                                                                        gdatimestamp->day = date->day;
                                                                }
+                                                       g_date_free (date);
                                                }
                                }
                        else if (gda_value_isa (v, GDA_TYPE_TIME))
@@ -1961,7 +1979,7 @@ GdaTimestamp
 
                                        if (time != NULL)
                                                {
-                                                       gdatimestamp = g_malloc0 (sizeof (GdaTimestamp));
+                                                       gdatimestamp = g_new0 (GdaTimestamp,1 );
                                                        gdatimestamp->hour = time->hour;
                                                        gdatimestamp->minute = time->minute;
                                                        gdatimestamp->second = time->second;
@@ -1996,7 +2014,12 @@ GDate
        v = gda_data_model_iter_get_value_at (iter, col);
        if (v == NULL)
                {
-                       g_warning ("Error on retrieving field's value at column %d.", col);
+                       GdaDataModel *data_model;
+
+                       g_object_get (G_OBJECT (iter), "data-model", &data_model, NULL);
+
+                       g_warning ("Error on retrieving field's value: «%s».",
+                                  gda_data_model_get_column_name (data_model, col));
                }
        else if (!gda_value_is_null (v))
                {
@@ -2049,7 +2072,12 @@ GDateTime
        v = gda_data_model_iter_get_value_at (iter, col);
        if (v == NULL)
                {
-                       g_warning ("Error on retrieving field's value at column %d.", col);
+                       GdaDataModel *data_model;
+
+                       g_object_get (G_OBJECT (iter), "data-model", &data_model, NULL);
+
+                       g_warning ("Error on retrieving field's value: «%s».",
+                                  gda_data_model_get_column_name (data_model, col));
                }
        else if (!gda_value_is_null (v))
                {
@@ -2104,7 +2132,12 @@ struct tm
        v = gda_data_model_iter_get_value_at (iter, col);
        if (v == NULL)
                {
-                       g_warning ("Error on retrieving field's value at column %d.", col);
+                       GdaDataModel *data_model;
+
+                       g_object_get (G_OBJECT (iter), "data-model", &data_model, NULL);
+
+                       g_warning ("Error on retrieving field's value: «%s».",
+                                  gda_data_model_get_column_name (data_model, col));
                }
        else if (!gda_value_is_null (v))
                {
@@ -2114,7 +2147,7 @@ struct tm
 
                        if (gdatimestamp != NULL)
                                {
-                                       ret = g_malloc0 (sizeof (struct tm));
+                                       ret = g_new0 (struct tm, 1);
 
                                        ret->tm_year = gdatimestamp->year - 1900;
                                        ret->tm_mon = gdatimestamp->month - 1;