我在MySQL (5.5.31)中有一个表,它有大约20M行。以下查询:
SELECT DISTINCT mytable.name name FROM mytable
LEFT JOIN mytable_c ON mytable_c.id_c = mytable.id
WHERE mytable.deleted = 0 ORDER BY mytable.date_modified DESC LIMIT 0,21
正在导致全表扫描,并解释说type是ALL,而额外信息是Using where; Using temporary; Using filesort。解释结果:
id sele
我尝试使用以下命令创建SSH隧道
ssh -L 3306:localhost:22 <hostip>
然后运行我的python脚本通过localhost进行连接
conn = MySQLdb.connect(host'localhost', port=3306, user='bob', passwd='na', db='test')
但是,我收到以下错误
(2002, "Can't connect to local MySQL server through socket '/var/lib/my
我在kubernetes中遇到了pods的问题。我有一个带有init容器的应用程序pod ( invoice ),它检查mysql pod ( invoice-mysql )是否正在运行invoice-mysql正在运行并准备就绪,但invoice pod中的init容器没有看到它
以下是init容器的日志
DB is not yet reachable;sleep for 10s before retry
DB is not yet reachable;sleep for 10s before retry
nc: bad address 'invoice-mysql'
nc:
mysql> explain select a.id,a.title from users c
-> straight_join iask a on c.id=a.uid
-> straight_join ianswer b on a.id=b.iaskid
->
-> where (c.last_check is null
我对带有范围的MYSQL多个复合索引有一些疑问。例如,如果我有以下索引:
Multiple column index in columns (A, B, C)
和下面的查询
WHERE A=2 AND B>5 AND C=3
问题:-索引将使用列(A,B,C)或仅使用(A,B)
那这个呢:
WHERE A=2 AND B IN (1,2,3) AND C=4
谢谢!