gistfile1.txt

# relationship('Comment', lazy="subquery")
# ------------------------------------------
# * 取得タイミング
#  * Entryを取得後、EntryのId列だけを取得して、そのId列のCommentのみを取得
#
# entry = Entry.query.filter_by(id=1).first() <- タイミングここ
# entry.comments
#
# * 発行SQL
# 1. SELECT *  FROM entries WHERE entries.id = 1 LIMIT 1
# 2. SELECT comments.*, anon_1.entries_id
#    FROM (
#           SELECT entries.id AS entries_id
#           FROM entries
#           WHERE entries.id = 1 LIMIT 1
#          ) AS anon_1
#    INNER JOIN comments
#    ON anon_1.entries_id = comments.entry_id
#    ORDER BY anon_1.entries_id