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MySQL SELECT only not null values
...hough...
SELECT val1 AS val
FROM your_table
WHERE val1 IS NOT NULL
UNION ALL
SELECT val2
FROM your_table
WHERE val2 IS NOT NULL
/*And so on for all your columns*/
The disadvantage of the above is that it scans the table multiple times once for each column. That may possibly be avoided by the b...
Is HttpClient safe to use concurrently?
In all the examples I can find of usages of HttpClient , it is used for one off calls. But what if I have a persistent client situation, where several requests can be made concurrently? Basically, is it safe to call client.PostAsync on 2 threads at once against the same instance of HttpClient .
...
Handler “ExtensionlessUrlHandler-Integrated-4.0” has a bad module “ManagedPipelineHandler” in its mo
...nformation Services (IIS).
The solution
I would recommend removing the call to SimpleWorkerRequest. Instead, you can use a Microsoft solution to make sure your web site automatically starts up after it recycles. What you need is the Microsoft Application Initialization Module for IIS 7.5. It is n...
How do I modify fields inside the new PostgreSQL JSON datatype?
...a":[null,{"b":[1,2,3]}]}'
For inserting into JSON array (while preserving all of the original values), the jsonb_insert() function can be used (in 9.6+; this function only, in this section):
SELECT jsonb_insert('{"a":[null,{"b":[1]}]}', '{a,1,b,0}', jsonb '2')
-- will yield jsonb '{"a":[null,{"b":[...
Deleting all files in a directory with Python
I want to delete all files with the extension .bak in a directory. How can I do that in Python?
7 Answers
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get list of pandas dataframe columns based on data type
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this doesn't work if all your dataframe columns are returning object type, regardless of their actual contents
– user5359531
Jul 17 '17 at 23:46
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How to check if all list items have the same value and return it, or return an “otherValue” if they
If all the items in a list have the same value, then I need to use that value, otherwise I need to use an “otherValue”. I can’t think of a simple and clear way of doing this.
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Using CSS to insert text
...
It is, but requires a CSS2 capable browser (all major browsers, IE8+).
.OwnerJoe:before {
content: "Joe's Task:";
}
But I would rather recommend using Javascript for this. With jQuery:
$('.OwnerJoe').each(function() {
$(this).before($('<span>').text("Joe'...
LINQ - Left Join, Group By, and Count
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.Count() will generate COUNT(*) which will count all the rows in that group, by the way.
– Mehrdad Afshari
Mar 29 '09 at 22:47
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HTML encoding issues - “” character showing up instead of “ ”
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Found another source This works in all browsers
– Richard Ayotte
Feb 19 '12 at 12:57
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