How to use Python left outer join using FOR/LIST/DICTIONARY comprehensions (not SQL)?

2024/11/13 15:15:44

I have two tuples, details below:

t1 = [
['aa'],
['ff'],
['er']
]

t2 = [
['aa', 11,],
['er', 99,]
]

and I would like to get results like these below using python method similar to SQL's LEFT OUTER JOIN:

res = [
['aa', 11,],
['ff',  0,],
['er', 99,]
]

Please help me with this.

Answer
d2 = dict(t2)
res = [[k[0], d2.get(k[0], 0)] for k in t1]
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