SQL

介紹利用 SQLBolt 網站快速學習SQL語法。 SQLBOLT Website: https://sqlbolt.com/ 這個網站可以讓初學SQL的人快速上手一些資料庫基本語法應用。 特色是具有互動式教學，讓學習者實際key in SQL指令完成各種query， 很推薦想初步學習SQL的人多利用。 課程簡介: Introduction to SQL SQL Lesson 1: SELECT queries 101 SELECT SQL Lesson 2: Queries with constraints (Pt. 1) WHERE SQL Lesson 3: Queries with constraints (Pt. 2) Constraints operators SQL Lesson 4: Filtering and sorting Query results SELECT DISTINCT / ORDER BY / LIMIT / OFFSET SQL Review: Simple SELECT Queries SQL Lesson 6: Multi-table queries with JOINs (INNER) JOIN ... ON ... SQL Lesson 7: OUTER JOINs LEFT / RIGHT / FULL JOIN ... ON ... SQL Lesson 8: A short note on NULLs IS/ IS NOT NULL SQL Lesson 9: Queries with expressions SELECT ... AS ... SQL Lesson 10: Queries with aggregates (Pt. 1) Aggregate s: COUNT / MIN / MAX / AVG / SUM SQL Lesson 11: Queries with aggregates (Pt. 2) GROUP BY ... HAVING ... SQL Lesson 12: Order of execution of a Query SQL Lesson 13: Inserting rows INSERT INTO ... VALUES ... SQL Lesson 14: Updating rows UPDATE ... SET ... SQL Lesson 15: Deleting rows DELETE FROM ... SQL Lesson 16: Creating tables CREATE TABLE IF NOT EXISTS ... SQL Lesson 17: Altering tables ALTER TABLE ... ADD / DROP / RENAME TO SQL Lesson 18: Dropping tables DROP TABLE IF EXISTS ... SQL Lesson X: To infinity and beyond! 上面的課程都是基本指令教學，按步驟上完就會有基本概念了。 使用SQL Query 開始下SQL query前，有幾點一定要先想清楚的， 清楚知道自己的目標跟需求資料。 目前擁有的資料有哪些。 清楚知道資料表的欄位意義。 產出的資料欄位格式定義。 都有想清楚後，就會讓 取資料 -> 建構資料 這條路順暢進行。

SQL

[SQL] 快速高效學習SQL語法 / Learn SQL With High Efficiency

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