用不相关的 table 中的数据填充交叉点 table

Question

我正在使用从网络上抓取的 json 数据构建一个关系数据库（多对多）。我有两个主数据库，一个有 909 行，另一个有 13 行。我需要将大 table 的 ID 与交集 table 中的小 table 的 ID 相匹配，对应于它们在 json 文件中的链接方式。我发现的问题是这些 table 没有任何关联，但我需要填充交集 table。除了需要几天时间的手工操作之外，我尝试或想到的任何东西都不会填充它。下面是 json 文件的一小部分示例。大 table 有课程信息，小 table 使用完成键。

[
{"number": "CHIN 242", "subject": "Chinese", "title": "Chinese Cinema and Chinese Modernity", "description": "From the fall of the Clestial Empire to the rise of China's economy today, Chinese cinema has witnessed many social changes in the modern era. This course will focus on the interaction between Chinese cinema and the process of modernization.", "fulfills": ["Human Expression\u2014Primary Texts", "Intercultural"]},

{"number": "CLAS 240", "subject": "Classics", "title": "Classical Mythology", "description": "A survey of the major myths and legends of ancient Greece and Rome.", "fulfills": ["Human Expression\u2014Primary Texts", "Quantitative"]},

{"number": "CLAS 250", "subject": "Classics", "title": "The World of Ancient Greece", "description": "A historical survey of ancient Greek culture from the Trojan War to the rise of Rome.", "fulfills": ["Human Expression\u2014Primary Texts", "Religion"]},

{"number": "CLAS 255", "subject": "Classics", "title": "Ancient Roman Culture", "description": "This course explores various cultural institutions and practices of the ancient Romans.", "fulfills": ["Human Expression\u2014Primary Texts", "Human Behavior"]},

{"number": "CLAS 265", "subject": "Classics", "title": "Greece and Rome on Film", "description": "This course explores the ways in which various events and episodes from Greek and Roman myth and history have been adapted for modern film and television.", "fulfills": ["Human Expression\u2014Primary Texts"]},

{"number": "CLAS 270", "subject": "Classics", "title": "Archaeology of Ancient Greece", "description": "An in-depth study of the archaeology of ancient Greece, with a focus on the high points of Greek civilization and material culture.", "fulfills": ["Historical", "Human Expression\u2014Primary Texts"]},

{"number": "CLAS 275", "subject": "Classics", "title": "Archaeology of Ancient Rome", "description": "This course explores the archaeology of ancient Rome from its early beginnings to its rapid growth into one of the world's largest empires.", "fulfills": ["Historical", "Human Expression\u2014Primary Texts"]},

{"number": "CLAS 300", "subject": "Classics", "title": "Classics and Culture", "description": "Using texts in translation, this course explores select aspects or themes from the cultures of ancient Greece and Rome.", "fulfills": ["Human Expression\u2014Primary Texts"]},
]

Answer 1

我找到了解决方法。要填充交集 table，运行对 id 的查询并在小 table 和 id 以及类似数字的简单内容上实现，然后运行 myDict = dict(map(reversed,cur.fetchall()))对于每个查询。从那里开始，使用 for 循环迭代 json 数据，然后使用嵌套 for 循环迭代 fulfills 和 cur.execute(insert into ...) 中的列表项。它看起来像这样：

cur.execute('select id, fulfills from reqs;')
dict1 = dict(map(reversed,cur.fetchall()))
cur.execute('select id, number from course;')
dict2 = dict(map(reversed,cur.fetchall()))
for x in geneds:
    for y in x:
        cur.execute('insert into table(course, req) values(%s, %s);', (dict2[x['number']], dict1[y]))

用不相关的 table 中的数据填充交叉点 table

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