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MySQL “between” clause not inclusive?
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From the MySQL-manual:
This is equivalent to the expression
(min <= expr AND expr <= max)
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How do I list all cron jobs for all users?
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You would have to run this as root, but:
for user in $(cut -f1 -d: /etc/passwd); do crontab -u $user -l; done
will loop over each user name listing out their crontab. The crontabs are owned by the respective users so you won't be able to see another u...
How do I change the data type for a column in MySQL?
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http://dev.mysql.com/doc/refman/5.1/en/alter-table.html
ALTER TABLE tablename MODIFY columnname INTEGER;
This will change the datatype of given column
Depending on how many columns you wish to modify it might be best to generate a scri...
What can you use Python generator functions for?
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Real World Example
Let's say you have 100 million domains in your MySQL table, and you would like to update Alexa rank for each domain.
First thing you need is to select your domain names from the database.
Let's say your table name is domains and column name is domain.
If you use SELECT...
使用Activity启动器组件 · App Inventor 2 中文网
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选择联系人
启动其他外部应用程序
了解如何设置 ActivityStarter 属性
在应用程序之间传递值
将活动启动器与两个 App Inventor 应用程序一起使用
该应用程序在设备上可用吗？
附录：为设计...
When and why are database joins expensive?
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MySQL, Oracle, SQL Server, Sybase, postgreSQL,etc. care not the order of joins. I've worked with DB2 and it also, to my knowledge, doesn't care what order you put them in. This is not helpful advice in the general case
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AJAX POST and Plus Sign ( + ) — How to Encode?
... and the plus sign (+) when i to try to save javascript "code examples" to mysql:
my solution (not the better way, but it works):
javascript:
function replaceAll( text, busca, reemplaza ){
while (text.toString().indexOf(busca) != -1)
text = text.toString().replace(busca,reemplaza);return text...
MySQL Error 1093 - Can't specify target table for update in FROM clause
...handle the OP's exact query, please see other answers to this question
In MySQL, you can't modify the same table which you use in the SELECT part.
This behaviour is documented at:
http://dev.mysql.com/doc/refman/5.6/en/update.html
Maybe you can just join the table to itself
If the logic is simple...
How to update column with null value
I am using mysql and need to update a column with a null value. I have tried this many different ways and the best I have gotten is an empty string.
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#1071 - Specified key was too long; max key length is 767 bytes
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767 bytes is the stated prefix limitation for InnoDB tables in MySQL version 5.6 (and prior versions). It's 1,000 bytes long for MyISAM tables. In MySQL version 5.7 and upwards this limit has been increased to 3072 bytes.
You also have to be aware that if you set an index on a big char ...