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How do I import CSV file into a MySQL table?
... MySQL table so that I can refactor into a sane format. I created a table called 'CSVImport' that has one field for every column of the CSV file. The CSV contains 99 columns , so this was a hard enough task in itself:
...
What is pseudopolynomial time? How does it differ from polynomial time?
...ng TSP takes time O(n · n!), which isn't polynomial time.
These runtimes all refer to some variable n that tracks the size of the input. For example, in selection sort, n refers to the number of elements in the array, while in TSP n refers to the number of nodes in the graph. In order to standardi...
How to send JSON instead of a query string with $.ajax?
... JSON.stringify(data),
contentType: "application/json",
complete: callback
});
Note that the JSON object is natively available in browsers that support JavaScript 1.7 / ECMAScript 5 or later. If you need legacy support you can use json2.
...
Vim: Creating parent directories on save
...ries for files like ftp://* and !isdirectory will prevent expensive mkdir call.
Update: sligtly better solution that also checks for non-empty buftype and uses mkdir():
function s:MkNonExDir(file, buf)
if empty(getbufvar(a:buf, '&buftype')) && a:file!~#'\v^\w+\:\/'
let dir=...
Unique BooleanField value in Django?
... save method of the model and if you've set the boolean to True, make sure all others are set to False.
from django.db import transaction
class Character(models.Model):
name = models.CharField(max_length=255)
is_the_chosen_one = models.BooleanField()
def save(self, *args, **kwargs):
...
Makefile经典教程(入门必备) - C/C++ - 清泛网 - 专注IT技能提升
...定义的值。如:
foo = $(bar)
bar = $(ugh)
ugh = Huh?
all:
echo $(foo)
我们执行“make all”将会打出变量$(foo)的值是“Huh?”( $(foo)的值是$(bar),$(bar)的值是$(ugh),$(ugh)的值是“Huh?”)可见,变量是可以使用后面的变量来...
Makefile经典教程(入门必备) - C/C++ - 清泛网 - 专注IT技能提升
...定义的值。如:
foo = $(bar)
bar = $(ugh)
ugh = Huh?
all:
echo $(foo)
我们执行“make all”将会打出变量$(foo)的值是“Huh?”( $(foo)的值是$(bar),$(bar)的值是$(ugh),$(ugh)的值是“Huh?”)可见,变量是可以使用后面的变量来...
Makefile经典教程(入门必备) - C/C++ - 清泛网 - 专注IT技能提升
...定义的值。如:
foo = $(bar)
bar = $(ugh)
ugh = Huh?
all:
echo $(foo)
我们执行“make all”将会打出变量$(foo)的值是“Huh?”( $(foo)的值是$(bar),$(bar)的值是$(ugh),$(ugh)的值是“Huh?”)可见,变量是可以使用后面的变量来...
Makefile经典教程(入门必备) - C/C++ - 清泛网 - 专注IT技能提升
...定义的值。如:
foo = $(bar)
bar = $(ugh)
ugh = Huh?
all:
echo $(foo)
我们执行“make all”将会打出变量$(foo)的值是“Huh?”( $(foo)的值是$(bar),$(bar)的值是$(ugh),$(ugh)的值是“Huh?”)可见,变量是可以使用后面的变量来...
Makefile经典教程(入门必备) - C/C++ - 清泛网 - 专注IT技能提升
...定义的值。如:
foo = $(bar)
bar = $(ugh)
ugh = Huh?
all:
echo $(foo)
我们执行“make all”将会打出变量$(foo)的值是“Huh?”( $(foo)的值是$(bar),$(bar)的值是$(ugh),$(ugh)的值是“Huh?”)可见,变量是可以使用后面的变量来...
