कौन सा अखंडता प्रतिबंध (integrity constraint) यह सुनिश्चित करता है कि डेटाबेस तालिका में प्रत्येक इकाई (पंक्ति) को विशिष्ट रूप से पहचानना आसान होना चाहिए?

The Dandi March, also known as the Salt Satyagraha, was led by which influential leader?

Which act formally granted independence to India, marking the end of British rule?

Who was the key figure in establishing the Indian National Congress?