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How do I check if an index exists on a table field in MySQL?
...
Try:
SELECT * FROM information_schema.statistics
WHERE table_schema = [DATABASE NAME]
AND table_name = [TABLE NAME] AND column_name = [COLUMN NAME]
It will tell you if there is an index of any kind on a certain column wi...
How to find the Windows version from the PowerShell command line
...fo. Powershell wrapper:
PS C:\> systeminfo /fo csv | ConvertFrom-Csv | select OS*, System*, Hotfix* | Format-List
OS Name : Microsoft Windows 7 Enterprise
OS Version : 6.1.7601 Service Pack 1 Build 7601
OS Manufacturer : Microsoft Corporation
OS Configuration : Stan...
When should null values of Boolean be used?
..."boolean", not "boolean" (mind styling), because in Oracle you usually use char(1) null with 'T' and 'F' values. So it may (with e.g., Hibernate type adapter) be null :)
– Grzegorz Grzybek
Jun 25 '12 at 7:58
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Convert a byte array to integer in Java and vice versa
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Not a solution for 3 byte stride. We can get Char, Short, Int. I suppose I could pad to 4 bytes and discard the 4th each time, but I would rather not.
– John
Jun 13 at 7:31
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Remove characters from NSString?
... This ONLY works if the 'spaces' are well behaved ASCII value=32 (%20) characters. To remove ALL possible white-space chars use Jim Dovey's solution below.
– Linasses
Apr 28 at 11:23
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Java: Integer equals vs. ==
...s small integers.
If the value p being boxed is true, false, a byte, a char in the range \u0000 to \u007f, or an int or short number between -128 and 127, then let r1 and r2 be the results of any two boxing conversions of p. It is always the case that r1 == r2.
Resources :
JLS - Boxing
O...
What is Scala's yield?
...in F# would be
[ for a in args -> a.toUpperCase ]
or
from a in args select a.toUpperCase
in Linq.
Ruby's yield has a different effect.
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Concatenating two std::vectors
...t;
#include <iostream>
#include <iterator>
int main(int argc, char** argv) {
std::vector<int> dest{1,2,3,4,5};
std::vector<int> src{6,7,8,9,10};
// Move elements from src to dest.
// src is left in undefined but safe-to-destruct state.
dest.insert(
dest.end(...
Python SQL query string formatting
...qualified a somewhere between Option 2 and Option 4
Code Sample:
sql = ("SELECT field1, field2, field3, field4 "
"FROM table "
"WHERE condition1=1 "
"AND condition2=2;")
Works as well with f-strings:
fields = "field1, field2, field3, field4"
table = "table"
conditions = "co...
What is the difference between UTF-8 and Unicode?
...r wants to use. Also, when a text editor program reads a file, it needs to select a text encoding scheme to decode it correctly. Same goes when you are typing and entering a letter, the text editor needs to know what scheme you use so that it will save it correctly.
– Cheng
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