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Add 2 hours to current time in MySQL?
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SELECT *
FROM courses
WHERE DATE_ADD(NOW(), INTERVAL 2 HOUR) > start_time
See Date and Time Functions for other date/time manipulation.
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Combine :after with :hover
I want to combine :after with :hover in CSS (or any other pseudo selector). I basically have a list and the item with the selected class has an arrow shape applied using :after . I want the same to be true for objects that are being hovered over but cant quite get it to work. Heres the cod...
in javascript, how can i get the last character in a string [duplicate]
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Since in Javascript a string is a char array, you can access the last character by the length of the string.
var lastChar = myString[myString.length -1];
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Block commenting in Ruby
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In TextMate, you can alt-drag vertically to select a column of text. This will duplicate the insertion point across all the lines you select, so you can insert or delete multiple #s at once.
UPDATE: Also in TextMate, assuming you have the right language selected, Cmd ...
How to reshape data from long to wide format
...mes(df) <- unique(dat1$name)
df
sqldf package:
library(sqldf)
sqldf('SELECT name,
MAX(CASE WHEN numbers = 1 THEN value ELSE NULL END) x1,
MAX(CASE WHEN numbers = 2 THEN value ELSE NULL END) x2,
MAX(CASE WHEN numbers = 3 THEN value ELSE NULL END) x3,
MAX(CASE WHEN numbe...
Count the occurrences of DISTINCT values
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SELECT name,COUNT(*) as count
FROM tablename
GROUP BY name
ORDER BY count DESC;
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Can I set a breakpoint on 'memory access' in GDB?
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Assuming the first answer is referring to the C-like syntax (char *)(0x135700 +0xec1a04f) then the answer to do rwatch *0x135700+0xec1a04f is incorrect. The correct syntax is rwatch *(0x135700+0xec1a04f).
The lack of ()s there caused me a great deal of pain trying to use watchpoints m...
Why do we have to specify FromBody and FromUri?
...When a parameter has [FromBody], Web API uses the Content-Type header
to select a formatter. In this example, the content type is
"application/json" and the request body is a raw JSON string (not a
JSON object). At most one parameter is allowed to read from the
message body.
This shoul...
How do I delete rows in a data frame?
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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...
How to pass values between Fragments
... I tried step 5, That i'm calling listactivity from fragment and after selecting item from that activity, i want to come back in fragment with selected file name. But its not working, its giving me Nullpointer Exception at onCreateView. Any solution on this please? This is my question stackoverf...