[libgda] DB: Adding checker to the property "table"

[Pavlo Solntsev <psolntsev src gnome org>]

commit fc889d6d82285097b96cfe2f080cf36a600521b0
Author: Pavlo Solntsev <p sun fun gmail com>
Date:   Wed Jun 3 14:40:17 2020 -0500

    DB: Adding checker to the property "table"

 libgda/gda-db-column.c | 9 +++++----
 libgda/gda-db-index.c  | 4 ++--
 2 files changed, 7 insertions(+), 6 deletions(-)
---
diff --git a/libgda/gda-db-column.c b/libgda/gda-db-column.c
index 758bf53dd..63b3c0020 100644
--- a/libgda/gda-db-column.c
+++ b/libgda/gda-db-column.c
@@ -188,7 +188,7 @@ gda_db_column_dispose (GObject *object)
   GdaDbColumn *self = GDA_DB_COLUMN (object);
   GdaDbColumnPrivate *priv = gda_db_column_get_instance_private (self);
 
-  g_object_unref (priv->mp_table);
+  if (priv->mp_table) g_object_unref (priv->mp_table);
 
   G_OBJECT_CLASS (gda_db_column_parent_class)->dispose (object);
 }
@@ -287,8 +287,9 @@ gda_db_column_set_property (GObject      *object,
       priv->m_scale = g_value_get_uint (value);
       break;
     case PROP_COLUMN_TABLE:
-      g_object_unref (priv->mp_table);
-      priv->mp_table = g_value_get_object (value);
+      if (priv->mp_table)
+        g_object_unref (priv->mp_table);
+      priv->mp_table = g_value_dup_object (value);
       break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
@@ -1320,7 +1321,7 @@ gda_db_column_create (GdaDdlModifiable *self,
   GdaDbTable *table = NULL;
   GdaDbColumn *column = GDA_DB_COLUMN (self);
 
-  const gchar *strtype;
+  const gchar *strtype = NULL;
 
   if (!gda_connection_is_opened (cnc))
     {
diff --git a/libgda/gda-db-index.c b/libgda/gda-db-index.c
index 229e38b4d..c20381368 100644
--- a/libgda/gda-db-index.c
+++ b/libgda/gda-db-index.c
@@ -129,7 +129,7 @@ gda_db_index_dispose (GObject *object)
   GdaDbIndex *self = GDA_DB_INDEX (object);
   GdaDbIndexPrivate *priv = gda_db_index_get_instance_private (self);
 
-  g_object_unref (priv->mTable);
+  if (priv->mTable) g_object_unref (priv->mTable);
 
   G_OBJECT_CLASS (gda_db_index_parent_class)->dispose (object);
 }
@@ -507,7 +507,7 @@ gda_db_index_create (GdaDdlModifiable *self,
 on_error:
   if (op) g_object_unref (op);
 
-  g_object_unref (table);
+  if (table) g_object_unref (table);
 
   gda_lockable_unlock (GDA_LOCKABLE (cnc));