大约有 44,000 项符合查询结果(耗时:0.0745秒) [XML]

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Check if table exists and if it doesn't exist, create it in SQL Server 2008

I am writing a Stored procedure in SQL Server 2008. I need to check if a table exists in the database. If it doesn't then I need to create it. ...
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How can I check if an argument is defined when starting/calling a batch file?

...ion, the exit needs a /B argument otherwise CMD.exe will quit. @echo off if [%1]==[] goto usage @echo This should not execute @echo Done. goto :eof :usage @echo Usage: %0 ^<EnvironmentName^> exit /B 1 share ...
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if else statement in AngularJS templates

... Angularjs (versions below 1.1.5) does not provide the if/else functionality . Following are a few options to consider for what you want to achieve: (Jump to the update below (#5) if you are using version 1.1.5 or greater) 1. Ternary operator: As suggested by @Kirk in the comm...
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Implicit type conversion rules in C++ operators

...C++ operators (for POD types) always act on objects of the same type. Thus if they are not the same one will be promoted to match the other. The type of the result of the operation is the same as operands (after conversion). If either is long double the other is promoted to long...
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Checking for empty queryset in Django

... if not orgs: # Do this... else: # Do that... share | improve this answer | follow ...
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Check if element exists in jQuery [duplicate]

How do I check if an element exists if the element is created by .append() method? $('elemId').length doesn't work for me. ...
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How do I check if a directory exists? “is_dir”, “file_exists” or both?

I want to create a directory if it does'nt exist already. 12 Answers 12 ...
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Test if a command outputs an empty string

How can I test if a command outputs an empty string? 11 Answers 11 ...
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Get the client IP address using PHP [duplicate]

... to get the IP address. The below both functions are equivalent with the difference only in how and from where the values are retrieved. getenv() is used to get the value of an environment variable in PHP. // Function to get the client IP address function get_client_ip() { $ipaddress = ''; ...
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How can I check if a command exists in a shell script? [duplicate]

I am writing my first shell script. In my script I would like to check if a certain command exists, and if not, install the executable. How would I check if this command exists? ...