title: “INNER JOIN” part: 1 topic_number: 15 slug: “inner-join” difficulty: “Beginner” prerequisites: “primary-foreign-keys, select-from-where” — INNER JOIN What Is It? INNER JOIN combines rows ...

title: “Primary Key and Foreign Key Concepts” part: 1 topic_number: 14 slug: “primary-foreign-keys” difficulty: “Beginner” prerequisites: “create-table” — Primary Key and Foreign Key Concepts Wha...

title: “HAVING vs WHERE” part: 1 topic_number: 13 slug: “having-vs-where” difficulty: “Beginner” prerequisites: “group-by, aggregate-functions” — HAVING vs WHERE What Is It? WHERE filters rows B...

title: “GROUP BY” part: 1 topic_number: 12 slug: “group-by” difficulty: “Beginner” prerequisites: “aggregate-functions” — GROUP BY What Is It? GROUP BY splits your data into categories, then cal...

title: “Aggregate Functions (COUNT, SUM, AVG, MIN, MAX)” part: 1 topic_number: 11 slug: “aggregate-functions” difficulty: “Beginner” prerequisites: “select-from-where” — Aggregate Functions What ...

title: “LIMIT” part: 1 topic_number: 10 slug: “limit” difficulty: “Beginner” prerequisites: “order-by” — LIMIT What Is It? LIMIT restricts the number of rows returned by a query. It’s perfect fo...

title: “ORDER BY” part: 1 topic_number: 9 slug: “order-by” difficulty: “Beginner” prerequisites: “select-from-where” — ORDER BY What Is It? ORDER BY sorts your query results. By default, SQL ret...

title: “Filtering Data” part: 1 topic_number: 8 slug: “filtering” difficulty: “Beginner” prerequisites: “select-from-where” — Filtering Data What Is It? Filtering refines your WHERE clause with ...

title: “SELECT with FROM and WHERE” part: 1 topic_number: 7 slug: “select-from-where” difficulty: “Beginner” prerequisites: “insert” — SELECT with FROM and WHERE What Is It? SELECT is the most i...

title: “DROP TABLE” part: 1 topic_number: 6 slug: “drop-table” difficulty: “Beginner” prerequisites: “create-table, alter-table” — DROP TABLE What Is It? DROP TABLE completely deletes a table fr...