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update columns values with column of another table based on condition [duplicate]
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it's not working in mysql
– cikatomo
Sep 30 '15 at 19:30
22
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SQL - Select first 10 rows only?
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select top 100 * from myTable
select top 100 colA, colB from myTable
In MySQL, use:
select ... order by num desc limit 10
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Node.js vs .Net performance
...ization
nodejs: 228,887
aspnet-stripped: 105,272
Single Query
nodejs-mysql: 88,597
aspnet-stripped-raw: 47,066
Multiple Queries
nodejs-mysql: 8,878
aspnet-stripped-raw: 3,915
Plain Text
nodejs: 289,578
aspnet-stripped: 109,136
In all cases, Node.js tends to be 2x+ faster than IIS.
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Is there any performance gain in indexing a boolean field?
...e an index, if you have too many records it doesn't use the index anyways.
MySQL not using index when checking = 1 , but using it with = 0
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How to implement the activity stream in a social network
...s to browse far back in time (if you even offer this)
I use a plain old MySQL table for dealing with about 15 million activities.
It looks something like this:
id
user_id (int)
activity_type (tinyint)
source_id (int)
parent_id (int)
parent_type (tinyint)
time ...
How to pull a random record using Django's ORM?
...e backend you're using." - any experience on diffrent DB backends? (sqlite/mysql/postgres)?
– kender
Jun 8 '09 at 9:37
4
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What is SQL injection? [duplicate]
...d queries, or applying your language/toolkit's escaping functions (such as mysql_real_escape_string() in PHP).
Once you understand SQL Injection you'll get the joke behind this cartoon.
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String isNullOrEmpty in Java? [duplicate]
...that when I tried to use StringUtils my IDE (Eclipse) imported it from com.mysql.jdbc.StringUtils which actually has an isNullOrEmpty(myStringObject) method.
ex.
import com.mysql.jdbc.StringUtils;
StringUtils.isNullOrEmpty(host)
Just another alternative for those who already have the MySQL conne...
Good Free Alternative To MS Access [closed]
...ess, you generally want a database server engine, like MS SQL, Postgresql, MySQL, Oracle, or their brethren. At the same time, those server engines are rarely if ever appropriate for a single-user desktop application.
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Java 理论与实践: 线程池与工作队列 - 更多技术 - 清泛网 - 专注C/C++及内核技术
... POP）、通过 JMS 队列或者可能通过轮询数据库。不管请求如何到达，服务器应用程序中经常出现的情况是：单个任务处理的时间很短而请求的数目却是巨大的。
构建服务器应用程序的一个过于简单的模型应该是：每当一个请求...