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How do I kill all the processes in Mysql “show processlist”?
...peration saves time. Do it in MySql itself:
Run these commands
mysql> select concat('KILL ',id,';') from information_schema.processlist
where user='root' and time > 200 into outfile '/tmp/a.txt';
mysql> source /tmp/a.txt;
Reference
---------edit------------
if you do not want to sto...
Difference between natural join and inner join
...+----------+
The INNER JOIN of TableA and TableB on Column1 will return
SELECT * FROM TableA AS a INNER JOIN TableB AS b USING (Column1);
SELECT * FROM TableA AS a INNER JOIN TableB AS b ON a.Column1 = b.Column1;
+------------+-----------+---------------------+
| a.Column1 | a.Column2 | ...
MySQL error 1449: The user specified as a definer does not exist
...finer for views
Run this SQL to generate the necessary ALTER statements
SELECT CONCAT("ALTER DEFINER=`youruser`@`host` VIEW ",
table_name, " AS ", view_definition, ";")
FROM information_schema.views
WHERE table_schema='your-database-name';
Copy and run the ALTER statements
How to change the...
Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
...irm this - I just updated a query with 4 joins on a 168,000 row database. Selecting just the first 100 rows with a SQL_CALC_FOUND_ROWS took over 20 seconds; using a separate COUNT(*) query took under 5 seconds (for both count + results queries).
– Sam Dufel
Ju...
How to update two tables in one statement in SQL Server 2005?
... by GROUP BY, HAVING, or DISTINCT clauses.
TOP is not used anywhere in the select_statement of the view together with the WITH CHECK OPTION clause.
In all honesty, though, you should consider using two different SQL statements within a transaction as per LBushkin's example.
UPDATE: My original ass...
LR性能测试结果样例分析 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...是否达到了预期的性能指标，其中又有哪些性能隐患，该如何解决。
图1- 1性能测试结果分析流程图
结果摘要
LoadRunner进行场景测试结果收集后，首先显示的该结果的一个摘要信息，如图1- 2所示。概要中列出了场景执行...
水果vs蔬菜智能分类器 - EdgeML图像识别项目 · App Inventor 2 中文网
...: Hackster.io
项目概述
本项目展示了如何使用 App Inventor 2 和 PersonalImageClassifier 扩展创建一个智能图像分类应用。该应用能够识别和区分水果与蔬菜，是 EdgeML（边缘机器学习）技术在移动端的实际应用案例。...
Optimal way to concatenate/aggregate strings
...Transact SQL, which should work fine in Azure.
;WITH Partitioned AS
(
SELECT
ID,
Name,
ROW_NUMBER() OVER (PARTITION BY ID ORDER BY Name) AS NameNumber,
COUNT(*) OVER (PARTITION BY ID) AS NameCount
FROM dbo.SourceTable
),
Concatenated AS
(
SELECT
...
XPath OR operator for different nodes
...
If you want to select only one of two nodes with union operator, you can use this solution:
(//bookstore/book/title | //bookstore/city/zipcode/title)[1]
share
...
MySQL INNER JOIN select only one row from second table
...have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL statements before so I want to know what i'm doing wrong. Appreciate the help
...