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Change One Cell's Data in mysql
How can I change the data in only one cell of a mysql table.
I have problem with UPDATE because it makes all the parameters in a column change but I want only one changed. How?
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Comparing two dictionaries and checking how many (key, value) pairs are equal
...t(json.dumps(diff, indent=4))
Output
{
"values_changed": {
"root['a']": {
"new_value": 2,
"old_value": 1
},
"root['nested']['b']": {
"new_value": 2,
"old_value": 1
}
}
}
Note about pretty-printing the result...
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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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...
Tree data structure in C#
...ation...
< 40 lines of code...
You just need to keep a reference to the root of the tree outside of the class,
or wrap it in another class, maybe rename to TreeNode??
share
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improve this answer
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How do I create a variable number of variables?
...s sometimes write code like this:
my_calculator.button_0 = tkinter.Button(root, text=0)
my_calculator.button_1 = tkinter.Button(root, text=1)
my_calculator.button_2 = tkinter.Button(root, text=2)
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The coder is then left with a pile of named variables, with a coding effort of O(m * n), where m ...
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...