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How to create a MySQL hierarchical recursive query
...s, path IDs, or self-joins.
MySQL 8+
with recursive cte (id, name, parent_id) as (
select id,
name,
parent_id
from products
where parent_id = 19
union all
select p.id,
p.name,
p.parent_id
from products p
inn...
Precision String Format Specifier In Swift
...
a simple way is:
import Foundation // required for String(format: _, _)
print(String(format: "hex string: %X", 123456))
print(String(format: "a float number: %.5f", 1.0321))
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impro...
argparse module How to add option without any argument?
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As @Felix Kling suggested use action='store_true':
>>> from argparse import ArgumentParser
>>> p = ArgumentParser()
>>> _ = p.add_argument('-f', '--foo', action='store_true')
>>> args = p.parse_args()
>>> args.foo
False
&g...
How can I use Guzzle to send a POST request in JSON?
... edited Aug 18 at 7:06
Valor_
2,49255 gold badges3939 silver badges8787 bronze badges
answered Mar 7 '14 at 8:56
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How do I find the location of the executable in C? [duplicate]
...proc/self/exe points me at the unfriendly path: /home/peeterj/views/peeterj_clang-7.vws/.s/00024/8000023250b8f17fllvm-tblgen
– Peeter Joot
Nov 30 '12 at 18:23
5
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demystify Flask app.secret_key
If app.secret_key isn't set, Flask will not allow you to set or access the session dictionary.
2 Answers
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Is there a goto statement in Java?
...reason to use goto that I can think of is this:
for (int i = 0; i < MAX_I; i++) {
for (int j = 0; j < MAX_J; j++) {
// do stuff
goto outsideloops; // to break out of both loops
}
}
outsideloops:
In Java you can do this like this:
loops:
for (int i = 0; i < MAX_I;...
Unable to install gem - Failed to build gem native extension - cannot load such file — mkmf (LoadErr
...ing so i had to run open /Library/Developer/CommandLineTools/Packages/macOS_SDK_headers_for_macOS_10.14.pkg
That didnt work for me at first because the version of CommandLineTools i had installed did not have the "Packages" folder. So i uninstalled and reinstalled like this:
rm -rf /Library/Devel...
How can I find where Python is installed on Windows?
...on about your installation:
import sys
print sys.executable
print sys.exec_prefix
I'm not sure what this will give on your Windows system, but on my Mac executable points to the Python binary and exec_prefix to the installation root.
You could also try this for inspecting your sys module:
impor...
How to search in array of object in mongodb
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Use $elemMatch to find the array of particular object
db.users.findOne({"_id": id},{awards: {$elemMatch: {award:'Turing Award', year:1977}}})
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