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第 65 章 Functions and Operators

目录

65.1. COUNT
65.2. group_concat() 列传行
65.3. UUID()
65.4. String
65.4.1. LEFT/RIGHT
65.4.2. RPAD/LPAD
65.4.3. CONCAT
65.4.4. CONCAT_WS
65.4.5. 链接所有字段
65.4.6. GROUP_CONCAT
65.4.7. replace
65.4.8. SUBSTRING
65.4.9. SUBSTRING_INDEX
65.4.10. AES_ENCRYPT / AES_DECRYPT
65.5. Date and Time
65.5.1. year/month/day hour:minite:second
65.5.2. Unix time
65.5.3. DATE_FORMAT
65.5.4. DATE_SUB/DATE_ADD
65.5.4.1. DATE_ADD
65.5.5. datediff / timediff
65.6. 数值函数
65.6.1. cast 类型转换
65.6.2. truncate 保留小数位数
65.6.3. MOD 求余
65.7. Control Flow Functions

65.1. 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';