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SELECT cust_name, cust_contact FROM customersWHERE cust_id IN (SELECT cust_id FROM orders #单独写多个分句，最后组成一个. WHERE order_num IN (SELECT... 阅读全文
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SELECT vend_id, COUNT(*) AS num_prods FROM products #GROUP BY子句可以包含任意数目的列，多行NULL值将分为一组GROUP BY vend_id; #GROUP BY子句必须出现在WHERE子句之后，ORDER BY子句之前。SELECT ... 阅读全文
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SELECT AVG(prod_price) AS avg_price FROM products; #AVG只能用于单个列求平均值，如想计算多个列，必须用多个AVG()SELECT AVG(prod_price) AS avg_price FROM productsWHERE vend_id = ... 阅读全文
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#文本处理函数SELECT vend_name, Upper(vend_name) AS vend_name_upcase FROM vendorsORDER BY vend_name;SELECT cust_name, cust_contact FROM customersWHERE Sounde... 阅读全文
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#字段(field)基本上和列(column)的意思相同SELECT Concat(vend_name, ' (', vend_country, ')') FROM vendorsORDER BY vend_name; #多数DBMS使用+或||来实现拼接，MySQL则使用Concat()函数来实现... 阅读全文
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SELECT prod_name FROM products WHERE prod_name REGEXP '1000' #检索列prod_name包含文本1000的所有行.ORDER BY prod_name;SELECT prod_name FROM products WHERE prod_na... 阅读全文
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SELECT prod_id, prod_name FROM products WHERE prod_name LIKE 'jet%'; #百分号(%)表示任何字符出现任意次数, %不能匹配值为NULL的行。SELECT prod_id, prod_name FROM products WHERE ... 阅读全文
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SELECT prod_id, prod_price, prod_name FROM products WHERE vend_id = 1003 AND prod_price = 10; #优先处理AND操作符SELECT prod_id, prod_price, prod_name FROM pr... 阅读全文
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SELECT prod_name, prod_price FROM products WHERE prod_price = 2.5;SELECT prod_name, prod_price FROM products WHERE prod_name = 'fuses'; #默认不区分大小写SELEC... 阅读全文
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SELECT prod_name FROM products ORDER BY prod_name;SELECT prod_id, prod_price, prod_name FROM products ORDER BY prod_price, prod_name;SELECT prod_id, p... 阅读全文
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SELECT prod_name FROM products;SELECT prod_id, prod_name, prod_price FROM products;SELECT * FROM products;SELECT DISTINCT vend_id FROM products;SELECT... 阅读全文
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########################### Populate customers table##########################INSERT INTO customers(cust_id, cust_name, cust_address, cust_city, cust_... 阅读全文
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CREATE DATABASE mysql_crash_course_db;USE mysql_crash_course_db;CREATE TABLE customers( cust_id int NOT NULL AUTO_INCREMENT, cust_name ... 阅读全文