diff --git a/field_collection.install b/field_collection.install
index c668b12..56fc449 100644
--- a/field_collection.install
+++ b/field_collection.install
@@ -110,7 +110,9 @@ function field_collection_update_7001() {
     // Set default to 0 temporarily.
     'initial' => 0,
   );
-  db_add_field('field_collection_item', 'revision_id', $revision_id_spec);
+  if (!db_field_exists('field_collection_item', 'revision_id')) {
+    db_add_field('field_collection_item', 'revision_id', $revision_id_spec);
+  }
 
   // Initialize the revision_id to be the same as the item_id.
   db_update('field_collection_item')
@@ -124,7 +126,9 @@ function field_collection_update_7001() {
     'not null' => TRUE,
     'default' => 0,
   );
-  db_add_field('field_collection_item', 'archived', $archived_spec);
+  if (!db_field_exists('field_collection_item', 'archived')) {
+    db_add_field('field_collection_item', 'archived', $archived_spec);
+  }
 
   // Create the new table. It is important to explicitly define the schema here
   // rather than use the hook_schema definition: http://drupal.org/node/150220.
@@ -153,7 +157,9 @@ function field_collection_update_7001() {
       ),
     ),
   );
-  db_create_table('field_collection_item_revision', $schema['field_collection_item_revision']);
+  if (!db_table_exists('field_collection_item_revision')) {
+    db_create_table('field_collection_item_revision', $schema['field_collection_item_revision']);
+  }
 
   // Fill the new table with the correct data.
   $items = db_select('field_collection_item', 'fci')
@@ -180,7 +186,9 @@ function field_collection_update_7001() {
 
       // Add a revision_id column.
       $revision_id_spec['description'] = 'The field collection item revision id.';
-      db_add_field($table, $revision_id_column, $revision_id_spec);
+      if (!db_field_exists($table, $revision_id_column)) {
+        db_add_field($table, $revision_id_column, $revision_id_spec);
+      }
 
       // Initialize the revision_id to be the same as the item_id.
       db_update($table)