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AND OR

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AND OR

If you can teach AND OR using Isha walking through AND OR, you know it. If you only know the heading, you don’t.

AND OR order — meaning → one AND OR step Isha can write from memory → one limit. Dumping ten features helps nobody.

Without AND OR, a small live site gets messy and Isha walking through AND OR is hard to trust.

Use AND OR when Isha walking through AND OR must stay clear. If a simpler SQL step works, use that instead.

Don’t do this with AND OR — copy-pasting AND OR without a dry-run. Interviewers spot it in ten seconds.

AND OR is not a lonely heading. Isha ties it to Isha walking through AND OR.

Viva for AND OR: what it is → one AND OR step Isha can write from memory → the mistake (copy-pasting AND OR without a dry-run).

Exam tip

Board: Isha walking through AND OR. Dry-run AND OR. Name the trap: copy-pasting AND OR without a dry-run.

AND OR — sample query

CREATE TABLE products (id INTEGER PRIMARY KEY, name TEXT, price REAL);
INSERT INTO products VALUES (1, 'Pen', 10), (2, 'Book', 200), (3, 'Bag', 50);
SELECT * FROM products
WHERE price BETWEEN 20 AND 150 AND name LIKE 'B%';

AND OR — wHERE combines predicates with AND/OR; LIKE does pattern match.

Short notes

DefAND OR — Isha uses it for Isha walking through AND OR in a small live site.
RuleAND OR → one AND OR step Isha can write from memory.
RememberAND OR + InnoDB (a small live site).
UseAND OR in a small live site (Isha walking through AND OR).
TrapAND OR — copy-pasting AND OR without a dry-run.
ExAND OR → Isha walking through AND OR.

CREATE TABLE products (id INTEGER PRIMARY KEY, name TEXT, price REAL); INSERT INTO products VALUES (1, 'Pen', 10), (2, 'Book', 200), (3, 'Bag', 50); SELECT * FROM products WHERE price BETWEEN 20 AND 150 AND name LIKE 'B%';

AND OR

AND OR — sample query

Short notes

Questions

AND OR

AND OR — sample query

Short notes

Questions