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Select distinct values from a table field
...ant any ordering to be applied to a query, not even the default ordering, call order_by() with no parameters.
and distinct() in the note where it discusses issues with using distinct() with ordering.
To query your DB, you just have to call:
models.Shop.objects.order_by().values('city').distinct(...
difference between foldLeft and reduceLeft in Scala
...e between reducing and folding
The difference is not the implementation at all, just look at the signatures.
The question doesn't have anything to do with Scala in particular, it's rather about the two concepts of functional programming.
Back to your question:
Here is the signature of foldLeft (c...
Unable to verify leaf signature
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Note: the following is dangerous, and will allow API content to be intercepted and modified between the client and the server.
This also worked
process.env['NODE_TLS_REJECT_UNAUTHORIZED'] = '0';
...
Database, Table and Column Naming Conventions? [closed]
... for Primary Key Columns, Hungarian-esque Constraint Prefixes and worst of all SPACES " " for multi-word table names. Additionally system tables for SQLServer use plurals so it seems AdventureWorks was the black sheep in this bunch.
– Marcus Pope
Mar 20 '12 at...
How to convert SQL Query result to PANDAS Data Structure?
... that will do the job:
from pandas import DataFrame
df = DataFrame(resoverall.fetchall())
df.columns = resoverall.keys()
You can go fancier and parse the types as in Paul's answer.
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improv...
How to pass arguments to a Button command in Tkinter?
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I personally prefer to use lambdas in such a scenario, because imo it's clearer and simpler and also doesn't force you to write lots of wrapper methods if you don't have control over the called method, but that's certainly a matter o...
uint8_t vs unsigned char
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It documents your intent - you will be storing small numbers, rather than a character.
Also it looks nicer if you're using other typedefs such as uint16_t or int32_t.
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WKWebView not loading local files under iOS 8
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They finally solved the bug! Now we can use -[WKWebView loadFileURL:allowingReadAccessToURL:].
Apparently the fix was worth some seconds in WWDC 2015 video 504 Introducing Safari View Controller
For iOS8 ~ iOS10 (Swift 3)
As Da...
Rename specific column(s) in pandas
I've got a dataframe called data . How would I rename the only one column header? For example gdp to log(gdp) ?
5 Answe...
How can I print the contents of a hash in Perl?
I keep printing my hash as # of buckets / # allocated.
How do I print the contents of my hash?
11 Answers
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