8 calls to db_drop_primary_key()

field_sql_storage_update_7001 in modules/field/modules/field_sql_storage/field_sql_storage.install
Remove the field_config_entity_type table and store 'entity_type' strings.
field_sql_storage_update_7002 in modules/field/modules/field_sql_storage/field_sql_storage.install
Fix primary keys in field revision data tables.
node_update_7016 in modules/node/node.install
Change {history}.nid to an unsigned int in order to match {node}.nid.
system_update_7065 in modules/system/system.install
Remove the default value for sid.
system_update_7086 in modules/system/system.install
Prepare the schema and data of the sessions table for hashed session ids.
trigger_update_7000 in modules/trigger/trigger.install
Alter the "hook" field and drop the "op field" of {trigger_assignments}.
trigger_update_7001 in modules/trigger/trigger.install
Increase the length of the "hook" field to 78 characters.
update_fix_d7_requirements in includes/update.inc
Perform Drupal 6.x to 7.x updates that are required for update.php to function properly.

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