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Remove characters except digits from string using Python?
...digs)
'1233344554552'
>>>
string.maketrans makes a translation table (a string of length 256) which in this case is the same as ''.join(chr(x) for x in range(256)) (just faster to make;-). .translate applies the translation table (which here is irrelevant since all essentially means iden...
SQLite: How do I save the result of a query as a CSV file?
...ex = False)
You can customize the query to only export part of the sqlite table to the CSV file.
You can also run a single command to export all sqlite tables to CSV files:
for table in c.execute("SELECT name FROM sqlite_master WHERE type='table';").fetchall():
t = table[0]
df = pd.read_sql...
How to know when UITableView did scroll to bottom in iPhone
I would like to know when a UITableView did scroll to bottom in order to load and show more content, something like a delegate or something else to let the controller know when the table did scroll to bottom.
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Introducing FOREIGN KEY constraint may cause cycles or multiple cascade paths - why?
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I had a table that had a circular relationship with others and i was getting the same error. Turns out it is about the foreign key which was not nullable. If key is not nullable related object must be deleted and circular relations d...
SQL Switch/Case in 'where' clause
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I'd say this is an indicator of a flawed table structure. Perhaps the different location types should be separated in different tables, enabling you to do much richer querying and also avoid having superfluous columns around.
If you're unable to change the structur...
Ship an application with a database
...re database from there. This is much quicker if the database has a lot of tables and other components. Upgrades are triggered by changing the database version number in the res/values/strings.xml file. Upgrades would then be accomplished by creating a new database externally, replacing the old dat...
Run a single migration file
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Note that if you do this, it probably won't update the schema_migrations table, but it seems like that's what you want anyway.
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Why is there extra padding at the top of my UITableView with style UITableViewStyleGrouped in iOS7
Starting in iOS7, there is additional space at the top of my UITableView 's which have a style UITableViewStyleGrouped .
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Is gcc std::unordered_map implementation slow? If so - why?
...red_map, the g++ implementation will automatically rehash to a larger hash table, and this would be a big drag on performance. If I remember correctly, unordered_map defaults to (smallest prime larger than) 100.
I didn't have chrono on my system, so I timed with times().
template <typename TEST...
Discuz! X3 论坛标题字数突破80的限制 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...你的表的前缀，还有修改前一定要备份！！！）
ALTER TABLE `pre_forum_post` CHANGE `subject` `subject` varchar(255) NOT NULL;
ALTER TABLE `pre_forum_rsscache` CHANGE `subject` `subject` varchar(255) NOT NULL;
ALTER TABLE `pre_forum_thread` CHANGE `subject` `subject` varchar(255...