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Can PostgreSQL index array columns?
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Yes you can index an array, but you have to use the array operators and the GIN-index type.
Example:
CREATE TABLE "Test"("Column1" int[]);
INSERT INTO "Test" VALUES ('{10, 15, 20}');
INSERT INTO "Test" VALUES ('{10, 20, 30}');
CREATE INDEX idx_test on "Test" USING GIN ("Col...
Error: Jump to case label
...the same issue but using a goto instead of a switch:
int main() {
if(rand() % 2) // Toss a coin
goto end;
int i = 42;
end:
// We either skipped the declaration of i or not,
// but either way the variable i exists here, because
// variable scopes are resolved at compi...
Evaluating string “3*(4+2)” yield int 18 [duplicate]
...NET framework that can evaluate a numeric expression contained in a string and return the result? F.e.:
14 Answers
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In C, how should I read a text file and print all strings
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The simplest way is to read a character, and print it right after reading:
int c;
FILE *file;
file = fopen("test.txt", "r");
if (file) {
while ((c = getc(file)) != EOF)
putchar(c);
fclose(file);
}
c is int above, since EOF is a negative number, an...
Initialization of all elements of an array to one default value in C++?
...that you used,
int array[100] = {-1};
says "set the first element to -1 and the rest to 0" since all omitted elements are set to 0.
In C++, to set them all to -1, you can use something like std::fill_n (from <algorithm>):
std::fill_n(array, 100, -1);
In portable C, you have to roll your...
How do I find where an exception was thrown in C++?
...t exception somewhere. All I get is a report of an exception being thrown, and no information as to where it was thrown. It seems illogical for a program compiled to contain debug symbols not to notify me of where in my code an exception was generated.
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Why should I use IHttpActionResult instead of HttpResponseMessage?
...eturning IHttpActionResult, and my answer demonstrates how you are able to convert the old HttpResponseMessage into an IHttpActionResult so that you can have the best of both worlds.
– AaronLS
May 26 '15 at 0:09
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How to edit incorrect commit message in Mercurial? [duplicate]
...evision you want to modify. Choose Modify History->Import MQ. That will convert all the revisions up to and including the selected revision from Mercurial changesets into Mercurial Queue patches. Select the Patch you want to modify the message for, and it should automatically change the screen to...
What was the strangest coding standard rule that you were forced to follow? [closed]
...this question I got almost always a definite yes you should have coding standards.
112 Answers
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Why do I need to override the equals and hashCode methods in Java?
...n conjunction with all hash-based collections, including HashMap, HashSet, and Hashtable.
Let's try to understand it with an example of what would happen if we override equals() without overriding hashCode() and attempt to use a Map.
Say we have a class like this and that two objects of MyClass are...