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MySQL Error 1215: Cannot add foreign key constraint
... @www.jensolsson.se You are correct, if the PK includes one or more string columns then they must use the same character set and collation. In this specific case the PK was an INT so the character set of the table and/or columns was not relevant.
– Ike Walker
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MySQL get row position in ORDER BY
... it.
SELECT t,COUNT(*) AS position FROM t
WHERE name <= 'search string' ORDER BY name
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What is the Scala identifier “implicitly”?
...erson, using a type class based approach:
trait Show[T] { def show(t: T): String }
object Show {
implicit def IntShow: Show[Int] = new Show[Int] { def show(i: Int) = i.toString }
implicit def StringShow: Show[String] = new Show[String] { def show(s: String) = s }
def ShoutyStringShow: Show[S...
Convert a python 'type' object to a string
I'm wondering how to convert a python 'type' object into a string using python's reflective capabilities.
5 Answers
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What is the X-REQUEST-ID http header?
...empotent message
processing in case of a retry
If you make it a random string, unique per request, it won't infringe on your privacy, nor enable tracking.
If you want to know more of what idempotency has to offer, read this insightful article.
N.B. As Stefan Kögl comments, this header is not ...
ASP.NET MVC 4 Custom Authorize Attribute with Permission Codes (without roles)
...rizeUserAttribute : AuthorizeAttribute
{
// Custom property
public string AccessLevel { get; set; }
protected override bool AuthorizeCore(HttpContextBase httpContext)
{
var isAuthorized = base.AuthorizeCore(httpContext);
if (!isAuthorized)
{
...
How to document a string type in jsdoc with limited possible values
I am having a function that accepts one string parameter. This parameter can have only one of a few defined possible values. What is the best way to document the same? Should shapeType be defined as enum or TypeDef or something else?
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Go Unpacking Array As Arguments
...ay.golang.org/p/2nN6kjHXIsd
I had a reason to unpack some vars from a map[string]string with single quotes around some of them as well as without. Here's the logic for it and the play link up top has the full working snippet.
func unpack(a map[string]string) string {
var stmt, val string
var x, y...
Objective-C Split()?
Is there any way to split strings in objective c into arrays? I mean like this - input string Yes:0:42:value into an array of (Yes,0,42,value)?
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How do I sort an NSMutableArray with custom objects in it?
...eter.
The two objects are just instances of Person. The third object is a string, e.g. @"birthDate".
This function returns an NSComparisonResult: It returns NSOrderedAscending if PersonA.birthDate < PersonB.birthDate. It will return NSOrderedDescending if PersonA.birthDate > PersonB.birthDat...