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Reset the database (purge all), then seed a database
Is there a rake command to wipe out the data in the database tables?
6 Answers
6
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ERROR 1452: Cannot add or update a child row: a foreign key constraint fails
...relationships involve a parent table that holds the
central data values, and a child table with identical values pointing
back to its parent. The FOREIGN KEY clause is specified in the child
table.
It will reject any INSERT or UPDATE operation that attempts to create
a foreign key value...
What is the proper way to format a multi-line dict in Python?
...uld use a similar but not identical format as your format 3. Here is mine, and why.
my_dictionary = { # Don't think dict(...) notation has more readability
"key1": 1, # Indent by one press of TAB (i.e. 4 spaces)
"key2": 2, # Same indentation scale as above
"key3": 3, # Keep this final c...
Does MongoDB's $in clause guarantee order
...the results
{ "$sort": { "weight": 1 } }
])
So that would be the expanded form. What basically happens here is that just as the array of values is passed to $in you also construct a "nested" $cond statement to test the values and assign an appropriate weight. As that "weight" value reflects t...
How can I create a copy of an object in Python?
... you can use the copy.deepcopy() function.
For more details about shallow and deep copying please refer to the other answers to this question and the nice explanation in this answer to a related question.
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Sorting an array of objects by property values
I've got the following objects using AJAX and stored them in an array:
30 Answers
30
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IPC performance: Named Pipe vs Socket
...y? I would prefer to use sockets because they can do two-way communication and are very flexible but will choose speed over flexibility if it is by considerable amount.
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Fastest way to find second (third…) highest/lowest value in vector or column
R offers max and min, but I do not see a really fast way to find another value in the order, apart from sorting the whole vector and then picking a value x from this vector.
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SQLite with encryption/password protection
I'm just learning to use SQLite and I was curious if such is possible:
9 Answers
9
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How do you get assembler output from C/C++ source in gcc?
... the preprocessor (cpp) over helloworld.c, perform the initial compilation and then stop before the assembler is run.
By default this will output a file helloworld.s. The output file can be still be set by using the -o option.
gcc -S -o my_asm_output.s helloworld.c
Of course this only works if y...