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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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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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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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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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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...
转型产品经理必看 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...文章。创办人人都是产品经理以来，每天都有很多人问我如何转型做产品经理、转型产品经理会遇到哪些问题，其实我一直没能回答好这个问题，因为我从运营转型产品经理的过程太顺利，并且转型的过程也没有做太多的思考和...
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...
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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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...
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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