大约有 13,700 项符合查询结果(耗时:0.0258秒) [XML]

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Can I set an opacity only to the background image of a div?

...e: linear-gradient(rgba(255,255,255,0.5), rgba(255,255,255,0.5)), url("your_image.png"); share | improve this answer | follow | ...
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add created_at and updated_at fields to mongoose schemas

Is there a way to add created_at and updated_at fields to a mongoose schema, without having to pass them in everytime new MyModel() is called? ...
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What's wrong with nullable columns in composite primary keys?

...key creation. If this was just a retrieval problem, you could use where pk_1 = 'a' and pk_2 = 'b' with normal values, and switch to where pk_1 is null and pk_2 = 'b' when there are nulls. – EoghanM Mar 15 '13 at 9:59 ...
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MySQL - length() vs char_length()

What's the main difference between length() and char_length() ? 2 Answers 2 ...
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How do I compare two strings in Perl?

...fied by the current locale if a legacy use locale (but not use locale ':not_characters') is in effect. See perllocale. Do not mix these with Unicode, only with legacy binary encodings. The standard Unicode::Collate and Unicode::Collate::Locale modules offer much more powerful solutions to collation ...
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What is INSTALL_PARSE_FAILED_NO_CERTIFICATES error?

...g=-d -v release install [signjar] Executing 'C:\Program Files\Java\jdk1.7.0_03\bin\jarsigner.exe' with arguments: [signjar] '-keystore' [signjar] 'C:\cygwin\home\Chloe\pairfinder\release.keystore' [signjar] '-signedjar' [signjar] 'C:\cygwin\home\Chloe\pairfinder\bin\PairFinder-release-unaligned.apk'...
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Handling a colon in an element ID in a CSS selector [duplicate]

JSF is setting the ID of an input field to search_form:expression . I need to specify some styling on that element, but that colon looks like the beginning of a pseudo-element to the browser so it gets marked invalid and ignored. Is there anyway to escape the colon or something? ...
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How do I use cascade delete with SQL Server?

...etting enabled. Something like: ALTER TABLE dbo.T2 DROP CONSTRAINT FK_T1_T2 -- or whatever it's called ALTER TABLE dbo.T2 ADD CONSTRAINT FK_T1_T2_Cascade FOREIGN KEY (EmployeeID) REFERENCES dbo.T1(EmployeeID) ON DELETE CASCADE ...
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When to use symbols instead of strings in Ruby?

...eference the symbol, saving memory. So every time the interpreter reads :my_key it can take it from memory instead of instantiate it again. This is less expensive than initializing a new string every time. You can get a list all symbols that are already instantiated with the command Symbol.all_sym...
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Calculating Distance between two Latitude and Longitude GeoCoordinates

...tic UnitOfLength Miles = new UnitOfLength(1); private readonly double _fromMilesFactor; private UnitOfLength(double fromMilesFactor) { _fromMilesFactor = fromMilesFactor; } public double ConvertFromMiles(double input) { return input*_fromMilesFactor; } ...