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Multiple Updates in MySQL
... answer assumes the ID is a unique key (can be primary as others said) but more importantly it assumes there are no other unique keys. If there are any, it can throw a spanner in the works.
– Steve Horvath
Dec 3 '14 at 5:43
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Alphabet range in Python
... I got: [chr(alpha+97) for alpha in range(0,27)] but this is much more intuitive. Doesn't require remembering that ascii of a is 97
– peterb
Aug 25 '16 at 5:45
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How to check if AlarmManager already has an alarm set?
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Show dialog from fragment?
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Unfortunately this approach is a bit more verbose than the classic managed dialogs approach of previous Android revisions, but it is now the preferred method. You can avoid referencing the Activity entirely by using the putFragment and getFragment methods of Fra...
Why is Java's SimpleDateFormat not thread-safe? [duplicate]
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How safe is it to store sessions with Redis?
... hard-disk. You can go through http://redis.io/topics/persistence to learn more, but at a high level, here are your options -
If you cannot afford losing any sessions, set appendfsync always in your configuration file. With this, Redis guarantees that any write operations are saved to the disk. T...
Why is it string.join(list) instead of list.join(string)?
...ee conceptually even if It makes sense codewise. list.join(string) appears more an object-oriented approach whereas string.join(list) sounds much more procedural to me.
– Eduardo Pignatelli
Jan 14 '18 at 15:35
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How can I remove a key and its value from an associative array?
...key3"]=> string(6) "value3" ["key4"]=> string(6) "value4" }
read more about array_diff: http://php.net/manual/en/function.array-diff.php
To remove an element by using index:
array_splice($arr, 1, 1);
var_dump($arr);
// array(1) { ["key3"]=> string(6) "value3" }
read more about ar...
Logical operators for boolean indexing in Pandas
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