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Fast way to discover the row count of a table in PostgreSQL
...ists in a given schema
TABLESAMPLE SYSTEM (n) in Postgres 9.5+
SELECT 100 * count(*) AS estimate FROM mytable TABLESAMPLE SYSTEM (1);
Like @a_horse commented, the newly added clause for the SELECT command might be useful if statistics in pg_class are not current enough for some reason. For ex...
How can I add new keys to a dictionary?
...oo': 'bar'}
>>> def f():
... d = {}
... for i in xrange(100):
... d['foo'] = i
...
>>> def g():
... d = {}
... for i in xrange(100):
... d.__setitem__('foo', i)
...
>>> import timeit
>>> number = 100
>>> min(timeit.repe...
How to do a SOAP Web Service call from Java class?
...CelsiusToFahrenheit>
<myNamespace:Celsius>100</myNamespace:Celsius>
</myNamespace:CelsiusToFahrenheit>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>
*/
// SOAP Body
SOAPBody ...
Initialise a list to a specific length in Python [duplicate]
...reate 2d list. If you create a list l = [[0]*10]*10], try change l[0][0] = 100, you will find that l[1][0], l[2][0] ... l[9][0] are all set to 100. It is because * replicates reference for object.
– John Wu
Sep 29 '14 at 13:31
...
CSS “color” vs. “font-color”
... border: solid 10px;
display: inline-block;
width: 60px;
height: 100px;
margin: 10px;
}
.innerElement2 {
background: currentColor;
display: inline-block;
width: 60px;
height: 100px;
margin: 10px;
}
<div class="element">
<div class="innerElement1"><...
How to file split at a line number [closed]
...
file_name=test.log
# set first K lines:
K=1000
# line count (N):
N=$(wc -l < $file_name)
# length of the bottom file:
L=$(( $N - $K ))
# create the top of file:
head -n $K $file_name > top_$file_name
# create bottom of file:
tail -n $L $file_name > bo...
How to scroll to bottom in a ScrollView on activity startup
...
Instead post() use postDelayed() with 100ms delay. it will work from any activitys life-cycle point.
– Vitaliy A
Jun 3 '15 at 13:39
add a...
Javascript date.getYear() returns 111 in 2011? [duplicate]
...
For years greater than or equal to 2000, the value returned by getYear is 100 or greater. For example, if the year is 2026, getYear returns 126.
For years between and including 1900 and 1999, the value returned by getYear is between 0 and 99. For example, if the year is 1976, getYear returns 76.
Fo...
How can I convert a series of images to a PDF from the command line on linux? [closed]
...he JPEG, resulting in generation loss. Use img2pdf instead; it's also 10–100 times faster.
– Robert Fleming
Jan 19 '17 at 20:29
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show 9 m...
Android - Round to 2 decimal places [duplicate]
...
One easy way to do it:
Double d;
Int i;
D+=0.005;
i=d*100;
Double b = i/100;
String s = b.toString():
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