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How to change the CHARACTER SET (and COLLATION) throughout a database?

... change database collation: ALTER DATABASE <database_name> CHARACTER SET utf8 COLLATE utf8mb4_0900_ai_ci; change table collation: ALTER TABLE <table_name> CONVERT TO CHARACTER SET utf8 COLLATE utf8mb4_0900_ai_ci; change column collation: ALTER TABLE <table_name&g...
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How to get the original value of an attribute in Rails

... Before rails 5.1 Appending _was to your attribute will give you the previous value. For rails 5.1+ Copied from Lucas Andrade's answer below: https://stackoverflow.com/a/50973808/9359123 Appending _was is deprecated in rails 5.1, now you should ap...
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Can a decorator of an instance method access the class?

...decorator, perhaps something like this (warning: untested code). def class_decorator(cls): for name, method in cls.__dict__.iteritems(): if hasattr(method, "use_class"): # do something with the method and class print name, cls return cls def method_decorator(v...
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How to find list of possible words from a letter matrix [Boggle Solver]

...n Python that I just coded up: #!/usr/bin/python class TrieNode: def __init__(self, parent, value): self.parent = parent self.children = [None] * 26 self.isWord = False if parent is not None: parent.children[ord(value) - 97] = self def MakeTrie(dict...
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Good example of livelock?

...deadlocks. This the output from console; 2016-09-12 21:31:45.065 :: [Maker_0:WAITING, Maker_1:WAITING, Maker_2:WAITING, Maker_3:WAITING, Maker_4:WAITING, Maker_5:WAITING, Maker_6:WAITING, Maker_7:WAITING, pool-7-thread-1:TIMED_WAITING, pool-7-thread-2:TIMED_WAITING, pool-8-thread-1:TIMED_WAITING, p...
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Combining C++ and C - how does #ifdef __cplusplus work?

...tive. Now, specifically regarding your numbered questions: Regarding #1: __cplusplus will stay defined inside of extern "C" blocks. This doesn't matter, though, since the blocks should nest neatly. Regarding #2: __cplusplus will be defined for any compilation unit that is being run through the C...
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How do I pass extra arguments to a Python decorator?

... it needs to return another function which is the actual decorator: def my_decorator(param): def actual_decorator(func): print("Decorating function {}, with parameter {}".format(func.__name__, param)) return function_wrapper(func) # assume we defined a wrapper somewhere ret...
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sqlalchemy unique across multiple columns

... declares those in the table definition, or if using declarative as in the __table_args__: # version1: table definition mytable = Table('mytable', meta, # ... Column('customer_id', Integer, ForeignKey('customers.customer_id')), Column('location_code', Unicode(10)), UniqueConstraint...
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How does Django's Meta class work?

...n [2]: User.Meta Out[2]: django.contrib.auth.models.Meta In [3]: User.Meta.__dict__ Out[3]: {'__doc__': None, '__module__': 'django.contrib.auth.models', 'abstract': False, 'verbose_name': <django.utils.functional.__proxy__ at 0x26a6610>, 'verbose_name_plural': <django.utils.functional...
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How to get the return value from a thread in python?

...cutor() as executor: future = executor.submit(foo, 'world!') return_value = future.result() print(return_value) share | improve this answer | follow ...