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第 25 章 Functions and Operators

目录

25.1. COUNT
25.2. group_concat() 列传行
25.3. UUID()
25.4. String
25.4.1. LEFT/RIGHT
25.4.2. RPAD/LPAD
25.4.3. CONCAT
25.4.4. CONCAT_WS
25.4.5. 链接所有字段
25.4.6. GROUP_CONCAT
25.4.7. replace
25.4.8. SUBSTRING
25.4.9. SUBSTRING_INDEX
25.4.10. AES_ENCRYPT / AES_DECRYPT
25.5. Date and Time
25.5.1. year/month/day hour:minite:second
25.5.2. Unix time
25.5.3. DATE_FORMAT
25.5.4. DATE_SUB/DATE_ADD
25.5.4.1. DATE_ADD
25.5.5. datediff / timediff
25.6. 数值函数
25.6.1. cast 类型转换
25.6.2. truncate 保留小数位数
25.6.3. MOD 求余
25.7. Control Flow Functions

25.1. 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';