oracle - What is the difference between varchar and varchar2? -

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वर्कर और varchar2 में क्या अंतर है?

अब के रूप में, वे समानार्थक शब्द हैं।

VARCHAR द्वारा ओरेकल के बीच अंतर का समर्थन करने के लिए आरक्षित है NULL और भविष्य में खाली स्ट्रिंग, जैसा कि ANSI मानक निर्धारित करता है।

VARCHAR2 एक NULL के बीच अंतर नहीं करता और खाली स्ट्रिंग, और कभी नहीं।

यदि आप खाली स्ट्रिंग पर निर्भर हैं और NULL एक ही बात है, तो आपको VARCHAR2 ।


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