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Why use multiple columns as primary keys (composite primary key)
...going to, in general, perform more poorly than a surrogate key'. Often an extra query is required to get the surrogate key of a relationship when you consider it. At which point it's a full extra round trip slower performance wise.
– ttugates
Apr 19 '19 at 20...
What is the effect of encoding an image in base64?
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@Blender But in my case when i convert a 70kb bitmap to string its becoming 500kb.Its not 37%.I have compressed a 5mb image to 70kb and then convert that compressed image to string that become 500kb.
– KJEjava48
Apr 19 '17 at 6:05
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Is there a performance difference between a for loop and a for-each loop?
...ts.
First, the classic way of looping through List:
for (int i=0; i < strings.size(); i++) { /* do something using strings.get(i) */ }
Second, the preferred way since it's less error prone (how many times have YOU done the "oops, mixed the variables i and j in these loops within loops" thing?...
Android - Set max length of logcat messages
... {
Log.v(TAG, "chunk " + i + " of " + chunkCount + ":" + sb.substring(4000 * i));
} else {
Log.v(TAG, "chunk " + i + " of " + chunkCount + ":" + sb.substring(4000 * i, max));
}
}
} else {
Log.v(TAG, sb.toString());
}
Edited to show the last string!
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Parsing JSON with Unix tools
...ivalent to curl --silent, whereas jq -r means jq --raw-output i.e. without string quotes.
– Serge Stroobandt
Oct 26 '18 at 21:52
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mysqldump data only
... you are using --databases ... option
--compact: if you want to get rid of extra comments
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How can I remove a trailing newline?
...uivalent of Perl's chomp function, which removes the last character of a string if it is a newline?
28 Answers
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How to copy a row and insert in same table with a autoincrement field in MySQL?
...INFORMATION_SCHEMA ... I wonder if you could do it as a sub-query and some string functions? Hmmm...
– Yzmir Ramirez
Feb 6 '12 at 6:35
1
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Difference between ref and out parameters in .NET [duplicate]
...nction. It's like if you could write this:
// This is not C#
public (bool, string) GetWebThing(string name, ref Buffer paramBuffer);
// This is C#
public bool GetWebThing(string name, ref Buffer paramBuffer, out string actualUrl);
Here's a more detailed list of the effects of each alternative:
Bef...
How to remove elements from a generic list while iterating over it?
...ist allows you to do a Remove(item) on your generic List:
List<String> strings = new List<string>() { "a", "b", "c", "d" };
foreach (string s in strings.ToArray())
{
if (s == "b")
strings.Remove(s);
}
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