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Counting null and non-null values in a single query
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If I understood correctly you want to count all NULL and all NOT NULL in a column...
If that is correct:
SELECT count(*) FROM us WHERE a IS NULL
UNION ALL
SELECT count(*) FROM us WHERE a IS NOT NULL
Edited to have the full query, after reading the comments :]
S...
Is it .yaml or .yml?
...ruling as you can get, but the habit of 8.3 is hard to get out of (and, appallingly, still occasionally relevant in 2013).
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What killed my process and why?
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I just wrote a program that malloc'd memory in an inifite loop. After the system got slow, "Killed" was displayed in the terminal and the process was terminated. The file /var/log/kern.log contained a lot of info about the termination. -Thanks for the...
What's the best manner of implementing a social activity stream? [closed]
...a social activity stream (Facebook is the most famous example). Problems/challenges involved are:
13 Answers
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MIN and MAX in C
Where are MIN and MAX defined in C, if at all?
14 Answers
14
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simple HTTP server in Java using only Java SE API
... GET/POST) in Java using just the Java SE API, without writing code to manually parse HTTP requests and manually format HTTP responses? The Java SE API nicely encapsulates the HTTP client functionality in HttpURLConnection, but is there an analog for HTTP server functionality?
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List directory in Go
... of everything in the current directory (folders are included but not specially marked - you can check if an item is a folder by using the IsDir() method):
package main
import (
"fmt"
"io/ioutil"
"log"
)
func main() {
files, err := ioutil.ReadDir("./")
if err != nil {
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Why is spawning threads in Java EE container discouraged?
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It is discouraged because all resources within the environment are meant to be managed, and potentially monitored, by the server. Also, much of the context in which a thread is being used is typically attached to the thread of execution itself. If y...
How to define a function in ghci across multiple lines?
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For guards (like your example), you can just put them all on one line and it works (guards do not care about spacing)
let abs n | n >= 0 = n | otherwise = -n
If you wanted to write your function with multiple definitions that pattern match on the arguments, like this:
fac...
Is it possible to refresh a single UITableViewCell in a UITableView?
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The OP isn't animating anything, so there's no need to call the begin/endupdates
– kubi
Jul 15 '13 at 17:38
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