6 calls to db_add_unique_key()

system_update_6019 in drupal-6.x/modules/system/system.install
Reconcile small differences in the previous, manually created mysql and pgsql schemas so they are the same and can be represented by a single schema structure.
system_update_6032 in drupal-6.x/modules/system/system.install
profile_fields.name used to be nullable but is part of a unique key and so shouldn't be.
system_update_6036 in drupal-6.x/modules/system/system.install
Change the search schema and indexing.
system_update_6043 in drupal-6.x/modules/system/system.install
Update table indices to make them more rational and useful.
system_update_6055 in drupal-6.x/modules/system/system.install
Improve indexes on the {url_alias} table.
_db_create_keys in drupal-6.x/includes/database.pgsql.inc