SQLAlchemy Bulk Select 查找现有记录

Question

我正在处理一些体育数据，并且有一个比赛字典，其键是比赛的唯一标识符（日期、主队 ID、客队 ID）（比赛的所有列 table） . 我想批量查询匹配项 table 并从字典中找到数据库中已有的所有键。我想这样做，但是对于字典中的所有键。

[(date, home_team, away_team), (date, home_team, away_team), ... N] = matches.keys()

*** only one match
Session.query(Match).filter_by(date=date, home_team=home_team, away_team=away_team)

编辑* 因此，按照建议我尝试了以下查询：

ins_matches = Session.query(Match).filter(tuple_(Match.date, Match.home_team, Match.away_team
                    ).in_(unq_keys)).all()

unq_keys 是包含 (date, home_team_id, away_team_id)

的元组列表

ProgrammingError: (psycopg2.ProgrammingError) operator does not exist: boolean = integer
LINE 3: ...es.home_team_id, teams.id = matches.away_team_id) IN (('2014...
                                                             ^
HINT:  No operator matches the given name and argument type(s). You might need to add explicit type casts.
 [SQL: 'SELECT matches.id AS matches_id, matches.date AS matches_date, matches.time AS matches_time, matches.league_id AS matches_league_id, matches.type AS matches_type, matches.home_team_id AS matches_home_team_id, matches.away_team_id AS matches_away_team_id, matches.stadium_id AS matches_stadium_id, matches.attendance AS matches_attendance, matches.duration AS matches_duration, matches.home_team_odds AS matches_home_team_odds, matches.away_team_odds AS matches_away_team_odds, matches.result AS matches_result \nFROM matches, teams \nWHERE (matches.date, teams.id = matches.home_team_id, teams.id = matches.away_team_id) IN ((%(param_1)s, %(param_2)s, %(param_3)s), (%(param_4)s, %(param_5)s, %(param_6)s), (%(param_7)s, %(param_8)s, %(param_9)s), (%(param_10)s, %(param_11)s, %(param_12)s), (%(param_13)s, %(param_14)s, %(param_15)s))'] [parameters: {'param_15': 17, 'param_11': 14, 'param_6': 18, 'param_5': 12, 'param_1': '2014-10-29', 'param_8': 11, 'param_4': '2014-10-28', 'param_13': '2014-10-28', 'param_7': '2014-10-28', 'param_14': 19, 'param_9': 20, 'param_10': '2014-10-29', 'param_2': 16, 'param_3': 15, 'param_12': 13}]

Answer 1

您可以使用 tuple_ expression combined with in_:

session.query(Match).filter(tuple_(Match.date, Match.home_team, Match.away_team).in_(list(matches.keys())))

请注意，这取决于 RDBMS 对复合 IN 结构的支持。

SQLAlchemy Bulk Select 查找现有记录

SQLAlchemy Bulk Select to find existing records

python

sqlalchemy

bulk