Replace indexes on term table:

OUT:
  INDEX ontology_idx (ontology_id),
  UNIQUE INDEX acc_ontology_idx (accession, ontology_id)

IN:
  UNIQUE INDEX accession_idx (accession),
  UNIQUE INDEX ontology_acc_idx (ontology_id, accession)

(i.e. require ontology term accessions to be unique across all
ontologies)