Tuple Relational Calculus (TRC) kya hota hai?

Tuple Relational Calculus (TRC) ek non-procedural query language hai DBMS mein.
Iska matlab hai ki hum ye batate hain ki hume kya chahiye, kaise lana hai ye nahi batate.

TRC mein hum tuples (rows) ko use karke batate hain ki kaunse condition wale rows hume result mein chahiye.

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 General Syntax (Structure)

Yahaan:

• -> T ek tuple variable hai (jaise ek placeholder for row).

• -> CONDITION(T) ek logical condition hai jo true honi chahiye taaki tuple result mein aaye.

 Example Table: Student

 Example Queries (TRC mein)

 Query 1: Sabhi students jinki age > 18 hai

Isme:

• S ek row ko represent karta hai.

• Student(S) ka matlab hai S Student table ka row hai.

• S.Age > 18 condition hai.

 Output:

 Query 2: Sirf un students ke naam jinki age 18 hai

Isme:

• Yahaan hum sirf Name chahte hain un students ka jinki age 18 hai.

 Output:

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 Important Baatein

• -> TRC logic par based hai.

• -> Ye declarative hai: hum batate hain kya chahiye, kaise chahiye nahi.

• -> Mostly theory mein use hota hai, real-world mein SQL zyada popular hai.

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 SQL aur TRC mein Difference:

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 TRC vs DRC