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Not Like Operator

Theory

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Not Like Operator

Not Like Operator is pattern matching. LIKE uses % and _. REGEXP / RLIKE uses regular expressions (e.g. name REGEXP '^[A-Z]'). They are not interchangeable.

REGEXP_LIKE, REGEXP_REPLACE, REGEXP_SUBSTR, REGEXP_INSTR are MySQL 8 helpers. Don’t write Java-style /pattern/g.

Trap — LIKE with regex stars. Trap: REGEXP on a huge unindexed column.

On the example next to this theory — Not Like Operator — wHERE combines predicates with AND/OR; LIKE does pattern match.

Exam tip

LIKE vs REGEXP in one sentence, plus one example.

Not Like Operator — 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%';

Not Like Operator — wHERE combines predicates with AND/OR; LIKE does pattern match.

Short notes

DefNot Like Operator matches text by a pattern.
RuleLIKE = % _. REGEXP = regular expressions.
TrapMixing LIKE wildcards with regex.

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%';

Not Like Operator

Not Like Operator — sample query

Short notes

Questions

Not Like Operator

Not Like Operator — sample query

Short notes

Questions