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ORA-00979 not a group by expression
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You must put all columns of the SELECT in the GROUP BY or use functions on them which compress the results to a single value (like MIN, MAX or SUM).
A simple example to understand why this happens: Imagine you have a database like th...
Distinct by property of class with LINQ [duplicate]
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You can use grouping, and get the first car from each group:
List<Car> distinct =
cars
.GroupBy(car => car.CarCode)
.Select(g => g.First())
.ToList();
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ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock'
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It's probably because MySQL is installed but not yet running.
To verify that it's running, open up Activity Monitor and under "All Processes", search and verify you see the process "mysqld".
You can start it by installing "MySQL...
What is the difference between the 'COPY' and 'ADD' commands in a Dockerfile?
What is the difference between the COPY and ADD commands in a Dockerfile, and when would I use one over the other?
13 A...
How do I check if a directory exists? “is_dir”, “file_exists” or both?
... should check both. There might be a regular file named 'foo', which would prevent you from creating a directory name 'foo'.
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How to search a Git repository by commit message?
...e commit log (across all branches) for the given text:
git log --all --grep='Build 0051'
To search the actual content of commits through a repo's history, use:
git grep 'Build 0051' $(git rev-list --all)
to show all instances of the given text, the containing file name, and the commit sha1.
F...
How do I get the path of a process in Unix / Linux
In Windows environment there is an API to obtain the path which is running a process. Is there something similar in Unix / Linux?
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How to get package name from anywhere?
I am aware of the availability of Context.getApplicationContext() and View.getContext() , through which I can actually call Context.getPackageName() to retrieve the package name of an application.
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Switching a DIV background image with jQuery
I am making an expand/collapse call rates table for the company I work for. I currently have a table with a button under it to expand it, the button says "Expand". It is functional except I need the button to change to "Collapse" when it is clicked and then of course back to "Expand" when it is clic...
How do I perform HTML decoding/encoding using Python/Django?
...se case, there are two answers to this. Here is its django.utils.html.escape function, for reference:
def escape(html):
"""Returns the given HTML with ampersands, quotes and carets encoded."""
return mark_safe(force_unicode(html).replace('&', '&').replace('<', '&l
t;').r...