SQL fundamentals
SQL asks the database for what you want and lets it work out how to fetch it. This course covers the clauses, the joins and the order the database actually runs them in.
What you'll learn
10 chapters, then the quiz
- 01What SQL isDeclarative queries against tables.
- 02SELECT and WHEREChoosing columns and filtering rows.
- 03NULLUnknown, not empty.
- 04Sorting and limitingORDER BY, LIMIT and paging.
- 05Aggregates and GROUP BYCollapsing many rows into one.
- 06JoinsCombining rows from two tables.
- 07Keys and relationshipsHow tables point at each other.
- 08Subqueries and CTEsQueries inside queries.
- 09Indexes and performanceWhy a query is slow.
- 10Changing dataINSERT, UPDATE, DELETE and transactions.
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