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Commands out of sync; you can't run this command now
I am trying to execute my PHP code, which calls two MySQL queries via mysqli, and get the error "Commands out of sync; you can't run this command now".
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select into in mysql
I am a MSSQL user and now I am converting my database to MySQL. I am writing the following query in MySQL:
2 Answers
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Query to count the number of tables I have in MySQL
...long wait time. In that case, login should be done with the option -A, ie: mysql -uroot -p -A, and the command will work fast.
– azurecorn
Jul 21 at 12:28
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Remove duplicate rows in MySQL
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This is no longer support in 5.7.4, dev.mysql.com/doc/refman/5.7/en/alter-table.html
– Ray Baxter
Nov 25 '15 at 20:59
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Throw an error in a MySQL trigger
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As of MySQL 5.5, you can use the SIGNAL syntax to throw an exception:
signal sqlstate '45000' set message_text = 'My Error Message';
State 45000 is a generic state representing "unhandled user-defined exception".
Here is a mo...
MySQL get the date n days ago as a timestamp
In MySQL, how would I get a timestamp from, say 30 days ago?
3 Answers
3
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Get records with max value for each group of grouped SQL results
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There's a super-simple way to do this in mysql:
select *
from (select * from mytable order by `Group`, age desc, Person) x
group by `Group`
This works because in mysql you're allowed to not aggregate non-group-by columns, in which case mysql just returns the first...
JAVA线程池管理及分布式HADOOP调度框架搭建 - 人工智能(AI) - 清泛IT社区，...
...了的东西，比如tomcat里的servlet就是线程，没有线程我们如何提供多用户访问呢？不过很多刚开始接触线程的开发攻城师却在这个上面吃了不少苦头。怎么做一套简便的线程开发模式框架让大家从单线程开发快速转入多线程开发...
Difference between VARCHAR and TEXT in MySQL [duplicate]
When we create a table in MySQL with a VARCHAR column, we have to set the length for it. But for TEXT type we don't have to provide the length.
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How to get UTF-8 working in Java webapps?
...s" those characters.
To get UTF-8 working under Java+Tomcat+Linux/Windows+Mysql requires the following:
Configuring Tomcat's server.xml
It's necessary to configure that the connector uses UTF-8 to encode url (GET request) parameters:
<Connector port="8080" maxHttpHeaderSize="8192"
maxThreads...