from infi.clickhouse_orm import *


class Fragment(Model):

    language = LowCardinalityField(StringField(), default='EN')
    document = LowCardinalityField(StringField())
    idx      = UInt64Field()
    word     = StringField()
    stem     = StringField()

    # An index for faster search by document and fragment idx
    index    = Index((document, idx), type=Index.minmax(), granularity=1)

    # The primary key allows efficient lookup of stems
    engine   = MergeTree(order_by=(stem, document, idx), partition_key=('language',))