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Counting null and non-null values in a single query
... to get it to work on another RDBMS):
select sum(case when a is null then 1 else 0 end) count_nulls
, count(a) count_not_nulls
from us;
Or:
select count(*) - count(a), count(a) from us;
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What Does 'Then' Really Mean in CasperJS
...r = require('casper').create();
casper.start();
casper.then(function step1() {
this.echo('this is step one');
});
casper.then(function step2() {
this.echo('this is step two');
});
casper.thenOpen('http://google.com/', function step3() {
this.echo('this is step 3 (google.com is loaded...
Unix command-line JSON parser? [closed]
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10 Answers
10
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Accessing bash command line args $@ vs $*
... parameters are quoted. Let me illustrate the differences:
$ set -- "arg 1" "arg 2" "arg 3"
$ for word in $*; do echo "$word"; done
arg
1
arg
2
arg
3
$ for word in $@; do echo "$word"; done
arg
1
arg
2
arg
3
$ for word in "$*"; do echo "$word"; done
arg 1 arg 2 arg 3
$ for word in "$@"; d...
How to define a function in ghci across multiple lines?
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125
For guards (like your example), you can just put them all on one line and it works (guards do ...
Getting an empty JQuery object
...ates an empty jQuery-object:
$([])
Update:
In newer versions of jQuery (1.4+), you can use:
$()
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How do shift operators work in Java? [duplicate]
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214
System.out.println(Integer.toBinaryString(2 << 11));
Shifts binary 2(10) by 11 times t...
LINQ with groupby and count
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412
After calling GroupBy, you get a series of groups IEnumerable<Grouping>, where each Group...
In Java, what is the best way to determine the size of an object?
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edited Jun 28 '16 at 18:24
Ravindra babu
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