Home | 简体中文 | 繁体中文 | 杂文 | 打赏(Donations) | 云栖社区 | OSChina 博客 | Facebook | Linkedin | 知乎专栏 | Github | Search | About

第 53 章 Functions and Operators

目录

53.1. COUNT
53.2. group_concat() 列传行
53.3. UUID()
53.4. String
53.4.1. LEFT/RIGHT
53.4.2. RPAD/LPAD
53.4.3. CONCAT
53.4.4. CONCAT_WS
53.4.5. 链接所有字段
53.4.6. GROUP_CONCAT
53.4.7. replace
53.4.8. SUBSTRING
53.4.9. SUBSTRING_INDEX
53.4.10. AES_ENCRYPT / AES_DECRYPT
53.5. Date and Time
53.5.1. year/month/day hour:minite:second
53.5.2. Unix time
53.5.3. DATE_FORMAT
53.5.4. DATE_SUB/DATE_ADD
53.5.4.1. DATE_ADD
53.5.5. datediff / timediff
53.6. 数值函数
53.6.1. cast 类型转换
53.6.2. truncate 保留小数位数
53.6.3. MOD 求余
53.7. Control Flow Functions

53.1. COUNT

count()

SELECT (SELECT count(1) FROM ecs_category) as 'Export category count',
	(SELECT count(1) FROM ecs_goods) as 'Goods count',
	(SELECT count(1) FROM ecs_goods_attr) as 'Attr count';