12 calls to db_drop_index()

comment_update_8000 in drupal/core/modules/comment/comment.install
Renames {comment}.language to {comment}.langcode.
comment_update_8002 in drupal/core/modules/comment/comment.install
Make *id fields unsigned.
dblog_update_8001 in drupal/core/modules/dblog/dblog.install
Make *id fields unsigned.
field_sql_storage_field_storage_update_field in drupal/core/modules/field_sql_storage/field_sql_storage.module
Implements hook_field_storage_update_field().
field_sql_storage_update_8000 in drupal/core/modules/field_sql_storage/field_sql_storage.install
Renames the 'language' column to 'langcode' in field data tables.
locale_update_8005 in drupal/core/modules/locale/locale.install
Update plural interface translations to new format.
node_update_8005 in drupal/core/modules/node/node.install
Make *id fields unsigned.
node_update_8018 in drupal/core/modules/node/node.install
Upgrade node schema to the standard entity SQL schema: delete old fields.
search_update_8001 in drupal/core/modules/search/search.install
Adds the langcode field and indexes to {search_dataset} and {search_index}.
taxonomy_update_8006 in drupal/core/modules/taxonomy/taxonomy.install
Change {taxonomy_term_data}.vid into a string holding the vocabulary machine name.
tracker_update_8001 in drupal/core/modules/tracker/tracker.install
Make *id fields unsigned.
update_prepare_d8_bootstrap in drupal/core/includes/update.inc
Performs extra steps required to bootstrap when using a Drupal 7 database.