How To Insert Values — SQL Technical Interview Questions & Answers

How To Insert Values

How To Insert Values

  • INSERT INTO students (roll, name, marks) VALUES (12, 'Asha', 72); adds one row. List the columns. Don’t rely on column order in the table — tomorrow someone ALTERs it.
  • Many rows: INSERT INTO students (roll, name, marks) VALUES (12,'Asha',72), (13,'Kabir',40); One statement, two rows.
  • AUTO_INCREMENT: skip that column, MySQL fills it. Duplicate PRIMARY KEY → error 1062. INSERT IGNORE skips the bad row. ON DUPLICATE KEY UPDATE changes the old row instead.
  • Trap: INSERT INTO students VALUES ('Asha', 12, 72) with columns in the wrong order. Trap: inserting NULL into NOT NULL.
  • On the example next to this theory: How To Insert Values — iNSERT adds rows. List columns explicitly for clarity.

Technical Interview Tip: INSERT INTO students (roll, name, marks) VALUES (12, 'Asha', 72);

Code Examples for How To Insert Values

How To Insert Values — sample query

CREATE TABLE products (id INTEGER PRIMARY KEY, name TEXT, price REAL);
INSERT INTO products (id, name, price) VALUES
  (1, 'Mouse', 499),
  (2, 'Keyboard', 999);
SELECT * FROM products;

How To Insert Values — iNSERT adds rows. List columns explicitly for clarity.

How to Explain How To Insert Values to an Interviewer

Write an INSERT.

INSERT INTO students (roll, name, marks) VALUES (12, 'Asha', 72);

How do you insert two rows?

Two tuples in VALUES (12,'Asha',72), (13,'Kabir',40)