Fix url index bug with renaming.

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/writelatex/model/db/sql/update/create/CreateIndexURLIndexStore.java

@@ -11,7 +11,7 @@ import java.sql.SQLException;
 public class CreateIndexURLIndexStore implements SQLUpdate {
 
     public static final String CREATE_INDEX_URL_INDEX_STORE =
-            "CREATE INDEX IF NOT EXISTS `project_path_index` ON `url_index_store`(`project_name`, `path`);\n";
+            "CREATE UNIQUE INDEX IF NOT EXISTS `project_path_index` ON `url_index_store`(`project_name`, `path`);\n";
 
     @Override
     public String getSQL() {

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/writelatex/model/db/sql/update/insert/AddURLIndexSQLUpdate.java

@@ -11,7 +11,7 @@ import java.sql.SQLException;
 public class AddURLIndexSQLUpdate implements SQLUpdate {
 
     private static final String ADD_URL_INDEX =
-            "INSERT INTO `url_index_store` (`project_name`, `url`, `path`) VALUES (?, ?, ?);\n";
+            "INSERT OR REPLACE INTO `url_index_store` (`project_name`, `url`, `path`) VALUES (?, ?, ?);\n";
 
     private final String projectName;
     private final String url;