PHP 與 MySql 入門學習指南

PHPPHP 與與 MySQLMySQL 入門學習指南入門學習指南第 30 章 資料表結合

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PHP 與 MySql 入門學習指南

MySQL 4.0 支援的 Join 語法table_reference, table_referencetable_reference [CROSS] JOIN table_referencetable_reference INNER JOIN table_reference join_conditiontable_reference STRAIGHT_JOIN table_referencetable_reference LEFT [OUTER] JOIN table_reference join_conditiontable_reference LEFT [OUTER] JOIN table_referencetable_reference NATURAL [LEFT [OUTER]] JOIN table_reference{table_reference LEFT OUTER JOIN table_reference ON conditional_expr }table_reference RIGHT [OUTER] JOIN table_reference join_conditiontable_reference RIGHT [OUTER] JOIN table_referencetable_reference NATURAL [RIGHT [OUTER]] JOIN table_reference

PHP 與 MySql 入門學習指南

JOIN 與 WHERE (1)SELECT first_name, order_id from customers AS C, orders AS O WHERE C.id=O.id;SELECT first_name, order_id from customers AS C INNER JOIN orders AS O ON C.id=O.id;

PHP 與 MySql 入門學習指南

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PHP 與 MySql 入門學習指南

JOIN 與 WHERE (2)SELECT column1,column2,.. FROM 【 table1 INNER JOIN table2 】ON 結合準則 WHERE condition_criteria

舊式【 WHERE 】語法SELECT C.first_name, C.last_Name, O.date, O.order_id FROM customers AS C, orders AS O WHERE C.id=O.id AND last_name = 'ponds';

新式【 JOIN 】 語法SELECT C.first_name, C.last_name, O.date, O.order_id FROM customers AS C INNER JOIN orders AS O ON C.id = O.id WHERE last_name = 'ponds';

PHP 與 MySql 入門學習指南

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PHP 與 MySql 入門學習指南

各類的 JOIN(1) 笛卡兒結合 [CROSS JOIN] 舊式 [WHERE] 語法

SELECT * FROM customers AS C,orders AS O;　新式 [JOIN] 語法

SELECT * FROM customers AS C CROSS JOIN orders AS O;

PHP 與 MySql 入門學習指南

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PHP 與 MySql 入門學習指南

各類的 JOIN(2)左結合 [LEFT JOIN]

SELECT * From customers AS C LEFT JOIN orders AS O ON C.id = O.id;

PHP 與 MySql 入門學習指南

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PHP 與 MySql 入門學習指南

各類的 JOIN(3)右結合 [RIGHT JOIN]SELECT * FROM customers AS C RIGHT JOIN orders AS O ON C.id=O.id;SELECT * FROM orders AS O LEFT JOIN customers AS C ON C.id=O.id;

PHP 與 MySql 入門學習指南

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PHP 與 MySql 入門學習指南

各類的 JOIN(4)自然左結合 [NATURAL LEFT JOIN]SELECT * From customers AS C LEFT JOIN orders AS O ON C.id = O.id;SELECT * FORM customers AS C NATURAL LEFT JOIN orders AS O;

PHP 與 MySql 入門學習指南

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