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Can I change a column from NOT NULL to NULL without dropping it?
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I tried with alter column and it didn't work with the latest mysql server. I tried with modify column and it worked. Strange...
– Kostas Andrianos
Aug 19 '17 at 15:29
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Concatenate multiple result rows of one column into one, group by another column [duplicate]
...st
FROM tbl
GROUP BY 1;
The 1 in GROUP BY 1 is a positional reference and a shortcut for GROUP BY movie in this case.
string_agg() expects data type text as input. Other types need to be cast explicitly (actor::text) - unless an implicit cast to text is defined - which is the case for all othe...
How to get current date time in milliseconds in android [duplicate]
i am trying to save my file with name as current date and time in milliseconds. and while reading file i want to read latest one.Here is the code
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How to make child process die after parent exits?
...t when its parent dies. This value is cleared for the child of a fork(2) and (since Linux 2.4.36 / 2.6.23) when executing a set-user-ID or set-group-ID binary.
– qrdl
Dec 10 '16 at 19:46
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Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
I have a pandas DataFrame and I want to delete rows from it where the length of the string in a particular column is greater than 2.
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How and why does 'a'['toUpperCase']() in JavaScript work?
...rCase() is a method of String.prototype
'a' is a primitive value, but gets converted into its Object representation
We have two possible notations to access object properties/methods, dot and bracket notation
So
'a'['toUpperCase'];
is the access via bracket notation on the property toUpperCase,...
how to change any data type into a string in python
...error like ordinal not in range(128). This was the case for me while I was converting list of string in language other than English
I resolved it by using unicode(object)
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How do I concatenate two text files in PowerShell?
...t would be
type file1.txt file2.txt file3.txt > files.txt
PowerShell converts the type command to Get-Content, which means you will get an error when using the type command in PowerShell because the Get-Content command requires a comma separating the files. The same command in PowerShell would...
Template default arguments
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@OlafDietsche but you can't have a template class and a non-template class with the same name, so the compiler should be able to decide by just looking at what the name is.
– Seth Carnegie
Mar 12 '13 at 23:13
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Determine if a sequence contains all elements of another sequence using Linq [duplicate]
... answered Nov 9 '11 at 12:54
AndersAnders
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