cannot name a primary key

misc-scripts/xref_mapping/sql/table.sql

@@ -237,7 +237,7 @@ CREATE TABLE checksum_xref (
   accession         CHAR(14) NOT NULL,
   checksum          CHAR(32) NOT NULL
 
-  PRIMARY KEY checksum_xref(checksum_xref_id),
+  PRIMARY KEY (checksum_xref_id),
   INDEX checksum_idx(checksum(10)
 ) COLLATE=latin1_swedish_ci ENGINE=InnoDB;