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๐— ๐—ฎ๐˜€๐˜๐—ฒ๐—ฟ ๐—ฆ๐—ค๐—Ÿ ๐—ณ๐—ผ๐—ฟ ๐—œ๐—ป๐˜๐—ฒ๐—ฟ๐˜ƒ๐—ถ๐—ฒ๐˜„๐˜€, ๐—™๐—ฎ๐˜€๐˜!

Here are 10 must-know SQL concepts:

โ— Stored Procedure vs. Function
Procedures allow DML; functions handle calculations only.

โ— Clustered vs. Non-Clustered Index
Clustered sorts data physically; non-clustered creates pointers.

โ— DELETE vs. TRUNCATE
DELETE is row-specific; TRUNCATE clears all rows fast.

โ— WHERE vs. HAVING
WHERE filters rows; HAVING filters after GROUP BY.

โ— Primary Key vs. Unique Key
Primary is unique & non-null; Unique allows one null.

โ— JOIN Types
INNER, LEFT, RIGHT, FULL JOINโ€”combine tables in different ways.

โ— Normalization Forms
Minimizes redundancy and improves data integrity.

โ— ACID Properties
Ensures reliable transactions with Atomicity, Consistency, Isolation, Durability.

โ— Indexes
Speeds up data retrieval; careful use is key.

โ— Subqueries
Nest queries within queries for flexible data retrieval.

Master these, and youโ€™re SQL-interview ready!
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