sql - I want to do INSERT without record in DB -

-

उपरोक्त प्रश्न का गैर-मूल अंग्रेजी से अंग्रेज़ी का अनुवाद:

यह एक प्रश्न है डेटाबेस में मान डालने का उपयोग करने के लिए सबसे तेज़ तरीका, जब मान पहले से डेटाबेस में हो सकता है INSERT असफल हो जायेगा जब मूल्य होता है और अद्यतन नहीं होगा जब यह नहीं है। इनमें से कौन सा विकल्प सबसे अधिक वांछनीय है?

  • पहले चुनें और INSERT या अद्यतन चुनें।
  • पहले डालें और अद्यतन करें यदि इसकी एक डुप्लिकेट त्रुटि है।

    • यदि उपर्युक्त के अलावा अन्य अच्छे विकल्प हैं, तो कृपया मुझे सिखाएं।

    पर्यावरण MySQL 4.1 का उपयोग करता है।

यदि आप ऐसा एक बयान में करना चाहते हैं (लगता है कि आप क्या चाहते हैं), मैं INSERT ... पर डुप्लिकेट कुंजी अद्यतन का उपयोग करने की सिफारिश करेगा सिंटेक्स, निम्न प्रकार से: 

  सारणी (IN, someothervalue) मूल्यों में INSERT (1, 'हाय माँ') डुप्लिकेट की कुंजी अद्यतन someothervalue = 'hi mom';

निर्दिष्ट कुंजी मान (या तो प्राथमिक कुंजी या अद्वितीय) के साथ कोई मौजूदा रिकॉर्ड नहीं है तो प्रारंभिक INSERT कथन निष्पादित होगा। यदि कोई रिकॉर्ड पहले से मौजूद है, तो निम्न UPDATE स्टेटमेंट ( someothervalue = 3 ) निष्पादित किया जाता है।

यह MySQL के सभी संस्करणों में समर्थित है अधिक जानकारी के लिए,

देखें

Comments

Post a Comment

Popular posts from this blog

c# - PInvoke of NetUserAdd returns 24 -

-
I am calling NetUserAdd and it is returning 24 for each call. Does anyone know 24 stands for? When I do not know what the error is, it is very difficult to debug it. I'm calling it a Windows XP machine running as a local administrator. I am also a local administrator on the target computer. I tried to do it with USER_INFO_1 and it worked fine. I need a level of control given by USER_INFO_2. This shows the return value for this call. They are further defined by numeric values. Unfortunately none of these values ​​= 24 I know this is a very specific question. I think I'm hoping to find a PInvoke / NetAddUser expert who can help me out there Here in case my code matters. [StructLayout (LayoutKind., Choracet = charset.unycode)] Public structure USER_INFO_2 {name of the public string; Public string password; Public int password_age; Public entities Private; Public string home_dir; Public string comment; Public integer flags; Public string script_path; Public int auth_...
Read more

NHibernate Passing Session to the Repository -

-
How do I go about passing a session for a repository class? We say that I have two projects 1) TestSite 2) Business Objects The Republican Business Objects Project is included in the project. The NHibernate session has been opened in the test site project. Now, I want to use the same session because the test site initiates the transaction on that session. Currently, I am using the following: var repository = New Customer Resor (_session); Of course, it looks ugly! I'm thinking in some way that a dependency injection frame can be tilted and I can be provided without entering the repository with the ejection object. In our WCF service, we actually use a unitofwork that wraps an operation and stores ISSN for that operation. . The repositories know how they are receiving a hint from the current unit of work under which they are running In case of testing we have a base test class, Those who are included in any test class, who touch the test database, we then control t...
Read more

objective c - Mouse events for an NSSegmentedCell subclass? -

-
I am trying to apply some basic tabs to the coco editor on which I am working. I am using an NSSegmentedControl and adding it as a tab. I'm using a custom NSSegmentedCell subclass for tabs to pull a little 'X' icon next to the text to close the tabs and now Till it is getting very greasy. However, I can not understand how to actually check the process of mouse events for tabs, whether someone has been placed on the 'x' icon (or clicked on) I tried to override the "mouse mood" in the NSSegmentedControl subclass, but for some strange reasons when I add a new segment to it (I set "setAcceptptsMouseMovedEvents" in awakeFromNib, do I have to set it somewhere else Is it?). NSSegmentedCells, there are no mouse tracking processing when the NSCell subclasses are done, on one hand, mouse tracking, which only starts when the control is clicked. So the question is, how do I process mouse events properly, either in NSSegmentedControl or in the NSSegme...
Read more