diff --git a/docker-compose.yml b/docker-compose.yml
index 0e22a8b..e31ab7c 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -1,4 +1,4 @@
-version: '3'
+---
 
 services:
   mariadb:
diff --git a/sql/000_ht_schema.sql b/sql/000_ht_schema.sql
index 9fa7888..1787869 100644
--- a/sql/000_ht_schema.sql
+++ b/sql/000_ht_schema.sql
@@ -320,9 +320,9 @@ CREATE TABLE `sources` (
 
 DROP TABLE IF EXISTS `oclc_concordance`;
 CREATE TABLE `oclc_concordance` (
-  `oclc` int(10) unsigned NOT NULL,
+  `variant` int(10) unsigned NOT NULL,
   `canonical` int(10) unsigned DEFAULT NULL,
-  KEY `oclc_c_oclc` (`oclc`),
+  KEY `oclc_c_var` (`variant`),
   KEY `oclc_c_canon` (`canonical`)
 ) ENGINE=InnoDB DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci;