大约有 41,000 项符合查询结果(耗时:0.0700秒) [XML]

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How to clear variables in ipython?

...r @ErdemKAYA comment. To erase a variable, use the magic command: %reset_selective <regular_expression> The variables that are erased from the namespace are the one matching the given <regular_expression>. Therefore %reset_selective -f a will erase all the variables containing a...
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What is the fastest or most elegant way to compute a set difference using Javascript arrays?

...t; 1; }; var fnVal = function (v, c) { return v; }; return myUtils.select(h, fnSel, fnVal); } }; This assumes that each and filter are defined for arrays, and that we have two utility methods: myUtils.keys(hash): returns an array with the keys of the hash myUtils.select(hash, fnSelect...
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Why do I get “Procedure expects parameter '@statement' of type 'ntext/nchar/nvarchar'.” when I try t

...r because @SQL needs to be NVARCHAR DECLARE @SQL VARCHAR(100) SET @SQL = 'SELECT TOP 1 * FROM sys.tables' EXECUTE sp_executesql @SQL So: DECLARE @SQL NVARCHAR(100) SET @SQL = 'SELECT TOP 1 * FROM sys.tables' EXECUTE sp_executesql @SQL ...
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What do I have to do to get Core Data to automatically migrate models?

...oordinator: %@",error); } Then you need to do a little trick in xCode: Select your xcdatamodel file Select the Design Menu at the top - then Data Model - then choose Add Model Version Your xcdatamodel file will then get moved into a new directory with the same name as your xcdatamodel file but w...
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Check if database exists in PostgreSQL using shell

...e vertical pipe | character (escaped from the shell with a backslash), and selects field 1. This leaves: my_db postgres template0 template1 grep -w matches whole words, and so won't match if you are searching for temp in this scenario. The -q option...
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belongs_to through associations

... I'd like to know myself. Everything I tried fired 3 selects. You can specify a "-> { joins :something }" lambda on an association. The join is fired but subsequently another select anyway. I wasn't able to tune this up. – Renra Oct 21 ...
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Get “Value” property in IGrouping

... For any selected group,you could call var selectedGroupValues=selectedGroup.SelectMany(x=>x); share | improve this answer ...
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Editing in the Chrome debugger

...ipt inside html files for me. Also, if you've added a folder to workspace, select the local js file, right-click and map that file to the network dito. – o-o Nov 5 '16 at 0:17 1 ...
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Is there a way to get a collection of all the Models in your Rails app?

.... EDIT: Just for fun, I found a way to list all classes Module.constants.select { |c| (eval c).is_a? Class } EDIT: Finally succeeded in listing all models without looking at directories Module.constants.select do |constant_name| constant = eval constant_name if not constant.nil? and constan...
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What is the difference between IQueryable and IEnumerable?

...es, meaning the custom query logic it receives, e.g., a predicate or value selector, is in the form of an expression tree instead of a delegate to a method. IEnumerable<T> is great for working with sequences that are iterated in-memory, but IQueryable<T> allows for out-of memory things ...