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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
... To reiterate, the SELECT N + 1 problem is, at its core: I have 600 records to retrieve. Is it faster to get all 600 of them in one query, or 1 at a time in 600 queries. Unless you're on MyISAM and/or you have a poorly normalized/poorly indexed schema (in which case the ORM isn't the prob...
How can I get the external SD card path for Android 4.0+?
...fat|fat32|ext3|ext4).*rw.*";
String s = "";
try {
final Process process = new ProcessBuilder().command("mount")
.redirectErrorStream(true).start();
process.waitFor();
final InputStream is = process.getInputStream();
final byte[] buffer = new by...
How to check if a stored procedure exists before creating it
...rocedural code anywhere you are able to run a query.
Just copy everything after AS:
BEGIN
DECLARE @myvar INT
SELECT *
FROM mytable
WHERE @myvar ...
END
This code does exactly same things a stored proc would do, but is not stored on the database side.
That's much like what ...
javac not working in windows command prompt
...
87
Windows OS searches the current directory and the directories listed in the PATH environment va...
python numpy machine epsilon
...given float type is to use np.finfo():
print(np.finfo(float).eps)
# 2.22044604925e-16
print(np.finfo(np.float32).eps)
# 1.19209e-07
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Browsers' default CSS for HTML elements
...oElem() {
stylo.dataset.hue = ((parseInt(stylo.value.substring(1), 16))/46666).toFixed(0)
media.style.cssText += ";filter:sepia(100%) saturate(1000%)grayscale(0)contrast(200%)hue-rotate("+ stylo.dataset.hue+"deg)invert("+(stylo.dataset.hue/3.6)+"%)"
}
styloElem()
body {
text-align:...
base64 encoded images in email signatures
...im Medora
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Convert NSData to String?
...\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7...
What's the difference between size_t and int in C++?
... graham.reedsgraham.reeds
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JS - get image width and height from the base64 code
...\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7...