大约有 40,000 项符合查询结果(耗时:0.0184秒) [XML]
Easiest way to copy a table from one database to another?
...
CREATE TABLE db1.table1 SELECT * FROM db2.table1
where db1 is the destination and db2 is the source
share
|
improve this answer
|
...
Retrieving the last record in each group - MySQL
...x, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn
FROM messages AS m
)
SELECT * FROM ranked_messages WHERE rn = 1;
Below is the original answer I wrote for this question in 2009:
I write the solu...
How to get all columns' names for all the tables in MySQL?
...
select * from information_schema.columns
where table_schema = 'your_db'
order by table_name,ordinal_position
share
|
impro...
MySQL high CPU usage [closed]
...ys do more harm than good.
Secondly I'd say you want to double check your MySQL users, just to make sure it's not possible for anyone to be connecting from a remote server. This is also a major security thing to check.
Thirdly I'd say you want to turn on the MySQL Slow Query Log to keep an eye on ...
Get Insert Statement for existing row in MySQL
... See this if you get the error mysqldump: Couldn't execute 'SELECT @@GTID_MODE': Unknown system variable 'GTID_MODE' (1193) gist.github.com/arun057/5556563
– Daniel Schaffer
Jul 12 '13 at 22:39
...
MySQL Orderby a number, Nulls last
...Place a minus sign (-) before the column name and switch the ASC to DESC:
SELECT * FROM tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC.
A good reference is here http://t...
对外网用户的squid代理+认证 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...
jiulongproxynew# make install
2、安装Apache,squid认证用户设置密码时使用apache的密码管理程序htpasswd
jiulongproxynew# cd /usr/ports/www/apache13
jiulongproxynew# make install
3、下载并安装squid
从http://www.squid-cache.org/Versions/v2/2.6/下载squid-2.6.STABLE1...
Error: Tablespace for table xxx exists. Please DISCARD the tablespace before IMPORT
I am fairly new to MySQL and I am getting a pretty interesting error on which I cannot find any help via google and the stackoverflow search.
...
Get all table names of a particular database by SQL query?
...different sql dbms deal with schemas.
Try the following
For SQL Server:
SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE' AND TABLE_CATALOG='dbName'
For MySQL:
SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE' AND TABLE_SCHEMA='dbN...
Rails 3: Get Random Record
...You can use the following trick on an indexed column (PostgreSQL syntax):
select *
from my_table
where id >= trunc(
random() * (select max(id) from my_table) + 1
)
order by id
limit 1;
share
|
...
