mysql - How to determine connection state of Perl DBI database handler -


पर्ल डीबीआई डाटाबेस हेन्डलर (कनेक्शन opend) की कनेक्शन स्थिति निर्धारित करने के लिए कैसे? जैसे कुछ। NET SqlConnection.State == ओपन हो सकता है कि 

  परिभाषित ($ dbh-> ("कुछ nop sql") करें)

लेकिन ऐसा कुछ हो सकता है, जिसमें sql nop कथन नहीं मिल सकता है का उपयोग करें।

आपसे यह पूछ सकते हैं कि डेटाबेस कॉल करने से जुड़ा हुआ है 

  $ dbh- & gt; पिंग ();

कुछ डीबी ड्राइवर पिंग को लागू नहीं करते हैं, लेकिन डीबीडी :: माइस्केल करता है वैकल्पिक रूप से, MySQL के लिए एक खाली चयन जैसे select 1 को चलाने के लिए है मैं MySQL मान रहा हूँ क्योंकि इससे आपके प्रश्न को टैग किया गया है। अन्य डेटाबेस में थोड़ा अलग जवाब होगा।


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