MySQL 数据透视表表

SELECT  
  period, 
  MAX(IF(day=1, CONCAT(subject,' ',room), '')) AS Mon, 
  MAX(IF(day=2, CONCAT(subject,' ',room), '')) AS Tue, 
  MAX(IF(day=3, CONCAT(subject,' ',room), '')) AS Wed, 
  MAX(IF(day=4, CONCAT(subject,' ',room), '')) AS Thu, 
  MAX(IF(day=5, CONCAT(subject,' ',room), '')) AS Fri 
FROM schedule 
GROUP BY period

MySQL 从csv文件插入mysql

LOAD DATA LOCAL INFILE '/file.csv' INTO TABLE `table_name` FIELDS TERMINATED BY ',' LINES TERMINATED BY '\n'
(field1,field2,etc)

MySQL 什么MySQL表有什么列

SELECT DISTINCT TABLE_NAME, COLUMN_NAME 
FROM INFORMATION_SCHEMA.COLUMNS
WHERE COLUMN_NAME LIKE '%column_name%'
AND TABLE_SCHEMA = 'database_name'

MySQL 找到重复的mysql字段值

SELECT name, COUNT(*) c FROM table GROUP BY name HAVING c > 1;

MySQL 重复的MySQL行略有变化

INSERT INTO wp_postmeta (post_id, meta_key, meta_value)
SELECT post_id, 'amazonS3_info' as meta_key, CONCAT('a:2:{s:6:"bucket";s:7:"bucketname";s:3:"key";s:', CHAR_LENGTH(meta_value) + 19,':"wp-content/uploads/', meta_value, '";}') FROM wp_postmeta WHERE meta_key = '_wp_attached_file'

MySQL 查找并替换MySQL

-- 1st example
UPDATE files SET filepath = REPLACE(filepath,'path/to/search','path/to/replace');
 
-- 2nd example
UPDATE customers SET address = REPLACE(address,'_CODE_',postcode);

MySQL 获取所有数据库的mysqldump

01  2  *  *  *    /usr/bin/mysqldump -A --opt -uadmin -p`cat /etc/psa/.psa.shadow` | gzip > /usr/share/drupalr/archives/mysqlbkp.sql.gz

MySQL 拿一个数据库的mysqldump

mysqldump -u <USERNAME> -p<PASSWORD> <DATABASE>  > <MYSQLDUMP>.sql

MySQL 具有递增ID的数字记录(将ID列添加到现有表)

SET @id := 0;
UPDATE users SET id = (@id := @id + 1) WHERE id = 0;

MySQL 将日期字段和时间字段转换为DateTime

select
evTitle as 'name',
concat(description,"\n",url) as description,
CASt(CONCAT(CAST(startDate as char),' ',cast(startTime as CHAR)) as datetime) as dtstart,
CASt(CONCAT(CAST(endDate as char),' ',cast(endTime as CHAR)) as datetime) as dtend,
evVenue as location,
evAddress as street,
evCity as city,
evState as state,
cast(NOW() as datetime) as modified_at,
cast(dateEntered as datetime ) as created_at,
'1' as author,
'127.0.0.1' as author_ip
from FTDevents;