class ActiveRecord::ConnectionAdapters::SchemaCreation

def visit_CreateIndexDefinition(o)
  index = o.index
  sql = ["CREATE"]
  sql << "UNIQUE" if index.unique
  sql << "INDEX"
  sql << o.algorithm if o.algorithm
  sql << "IF NOT EXISTS" if o.if_not_exists
  sql << index.type if index.type
  sql << "#{quote_column_name(index.name)} ON #{quote_table_name(index.table)}"
  sql << "USING #{index.using}" if supports_index_using? && index.using
  sql << "(#{quoted_columns(index)})"
  sql << "WHERE #{index.where}" if supports_partial_index? && index.where
  sql.join(" ")
end