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How to convert timestamp to datetime in MySQL?
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SELECT from_unixtime( TIMESTAMP( "2011-12-01", "22:01:23.048" ) ) doesn't work. why? using v5.6
– Janus Troelsen
Feb 4 '14 at 18:44
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Can a JSON value contain a multiline string
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Check out the specification! The JSON grammar's char production can take the following values:
any-Unicode-character-except-"-or-\-or-control-character
\"
\\
\/
\b
\f
\n
\r
\t
\u four-hex-digits
Newlines are "control characters" so, no, you may not have a literal newli...
How do I delete rows in a data frame?
... :
mydata[-seq(2, nrow(mydata), by = 2) , ]
Or if you want to subset by selecting odd numbers:
mydata[which(1:nrow(mydata) %% 2 == 1) , ]
Or if you want to subset by selecting odd numbers, version 2:
mydata[which(1:nrow(mydata) %% 2 != 0) , ]
Or if you want to subset by filtering even numbe...
Linq with group by having count
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from c in db.Company
group c by c.Name into grp
where grp.Count() > 1
select grp.Key
Or, using the method syntax:
Company
.GroupBy(c => c.Name)
.Where(grp => grp.Count() > 1)
.Select(grp => grp.Key);
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What is the effect of encoding an image in base64?
...e64 is the better choice.
Size of base64-images
Base64 uses 64 different characters and this is 2^6. So base64 stores 6bit per 8bit character. So the proportion is 6/8 from unconverted data to base64 data. This is no exact calculation, but a rough estimate.
Example:
An 48kb image needs around 64...
How to sum up an array of integers in C#
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Point taken. Yet, the following saves 18 chars compared to your sample: foreach (int i in arr) sum += i;
– Jørn Schou-Rode
Mar 16 '10 at 11:44
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jQuery : eq() vs get()
... the DOM elements matched by the jQuery object.
http://api.jquery.com/eq-selector/
Description: Select the element at index n within the matched set.
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How to use PrimeFaces p:fileUpload? Listener method is never invoked or UploadedFile is null / throw
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Looks like javax.faces.SEPARATOR_CHAR must not be equal to _
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Replace input type=file by an image
... be updated with the filename or at least a message that the file has been selected successfully. The user has no visual input on what happened after he selected the file. Could this be done please? Perhaps change to a different image, when a file is chosen?
– JoaMika
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What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
... using Standard SQL.
An obvious omission is the equivalent using EXCEPT:
SELECT a FROM table1
EXCEPT
SELECT a FROM table2
Note in Oracle you need to use the MINUS operator (arguably a better name):
SELECT a FROM table1
MINUS
SELECT a FROM table2
Speaking of proprietary syntax, there may also ...