Choose the SQL commands to perform following operations on a relation R :
I : Retain Relation R in database, but delete all tuples in R.
II : Delete all information about R in Database.
एक रिलेशन R पर निम्न क्रियाएँ करने के लिए SQL कमांड्स का चुनाव कीजिए :
I : रिलेशन R को डाटाबेस में रखें परन्तु उसके सारे टपल्स डिलीट करें।
II : रिलेशन R के बारे में समस्त सूचनाएँ डाटाबेस से डिलीट करें।
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Show answer & explanation
Correct answer: B. I : Delete from R; II : Drop table R
Explanation
DELETE FROM R removes every tuple but keeps the table; DROP TABLE R removes the table and its definition from the database.
DELETE FROM R सभी टपल हटाता है पर टेबल रहती है; DROP TABLE R पूरी टेबल व उसकी परिभाषा हटा देता है।
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