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Entity Framework - Code First - Can't Store List

... List of entities? how will the mapping be saved? – A_Arnold Aug 6 '18 at 15:16 Depends - most likely to a separate ta...
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How to inherit from a class in javascript?

...sole issue?) // In the Chrome console you should be able to drill down the __proto__ chain // You can also look down the proto chain with Object.getPrototypeOf // (Equivalent to tiger.__proto__) console.log( Object.getPrototypeOf(tiger) ); // Mammal console.log( Object.getPrototypeOf(Object.getPro...
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MySQL get the date n days ago as a timestamp

... DATE_SUB will do part of it depending on what you want mysql> SELECT DATE_SUB(NOW(), INTERVAL 30 day); 2009-06-07 21:55:09 mysql> SELECT TIMESTAMP(DATE_SUB(NOW(), INTERVAL 30 day)); 2009-06-07 21:55:09 mysql> SELECT U...
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JSONDecodeError: Expecting value: line 1 column 1 (char 0)

...on struct = {} try: try: #try parsing to dict dataform = str(response_json).strip("'<>() ").replace('\'', '\"') struct = json.loads(dataform) except: print repr(resonse_json) print sys.exc_info() Note: Quotes within the data must be properly escaped ...
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How to use single storyboard uiviewcontroller for multiple subclass

... The code of line we are looking for is: object_setClass(AnyObject!, AnyClass!) In Storyboard -> add UIViewController give it a ParentVC class name. class ParentVC: UIViewController { var type: Int? override func awakeFromNib() { if type = 0 { ...
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Converting strings to floats in a DataFrame

... NOTE: pd.convert_objects has now been deprecated. You should use pd.Series.astype(float) or pd.to_numeric as described in other answers. This is available in 0.11. Forces conversion (or set's to nan) This will work even when astype will ...
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What is the difference between HTTP_HOST and SERVER_NAME in PHP?

What is the difference between HTTP_HOST and SERVER_NAME in PHP? 10 Answers 10 ...
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A better similarity ranking algorithm for variable length strings

...ren) so that I can use it in my PostgreSQL queries: CREATE FUNCTION string_similarity(str1 varchar, str2 varchar) RETURNS float8 AS ' str1.downcase! pairs1 = (0..str1.length-2).collect {|i| str1[i,2]}.reject { |pair| pair.include? " "} str2.downcase! pairs2 = (0..str2.length-2).collect {|i| st...
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No mapping found for field in order to sort on in ElasticSearch

... After digging more, I found the solution as given below. ignore_unmapped should be explicitly set to true in the sort clause. "sort" : [ { "rating": {"order" : "desc" , "ignore_unmapped" : true} }, { "price": {"order" : "asc" , "missing" : "_last" , "ignore_unmapped" : tru...
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Best way to serialize an NSData into a hexadeximal string

...rsion.h #import <Foundation/Foundation.h> @interface NSData (NSData_Conversion) #pragma mark - String Conversion - (NSString *)hexadecimalString; @end NSData+Conversion.m #import "NSData+Conversion.h" @implementation NSData (NSData_Conversion) #pragma mark - String Conversion - (NSStr...