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GroupBy pandas DataFrame and select most common value
.... To clean the data I have to group by data frame by first two columns and select most common value of the third column for each combination.
...
How to tell Xcode where my info.plist and .pch files are
...g to add my discoveries here as it is slightly different for Xcode 4.2:
Select your project
In the left side of the middle pane, select your app under "Targets"
Select the tab "Build Settings"
Search the following keywords: "info.plist" and "pch"
At this point it should be pretty clear which are ...
Which SQL query is faster? Filter on Join criteria or Where clause?
...INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x
ON x.TableAID = a.ID
AND a.ID = 1
LEFT JOIN
TableB b
ON x.TableBID = b.ID
or this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x...
What's the difference between disabled=“disabled” and readonly=“readonly” for HTML form input fields
...
Not all form elements have a readonly attribute. Most notable, the <SELECT> , <OPTION> , and <BUTTON> elements do not have readonly
attributes (although they both have disabled attributes)
Browsers provide no default overridden visual feedback that the form element is read ...
The target … overrides the `OTHER_LDFLAGS` build setting defined in `Pods/Pods.xcconfig
...n your project, find Target -> Build Settings -> Other Linker Flags, select Other Linker Flags, press delete(Mac Keyboard)/Backspace(Normal keyboard) to recover the setting. It works for me.
Example:
Before
After
...
How to express a NOT IN query with ActiveRecord/Rails?
...rums, lambda { |forums| { :conditions => ['forum_id not in (?)', forums.select(&:id).join(',')] }
# in your controller
Topic.not_in_forums(@forums)
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Rails: Using greater than/less than with a where statement
...s behavior.
User.where(id: 201..Float::INFINITY)
will generate the SQL
SELECT `users`.* FROM `users` WHERE (`users`.`id` >= 201)
The same can be done for less than with -Float::INFINITY.
I just posted a similar question asking about doing this with dates here on SO.
>= vs >
To avo...
Delete all records in a table of MYSQL in phpMyAdmin
...ampserver 2.2. When I want to delete all records of a table in phpMyAdmin (select all) it deletes only one record not all records. Why it does not delete all records?
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How to get a value of an element by name instead of ID
...
Use the name attribute selector:
$("input[name=nameGoesHere]").val();
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update columns values with column of another table based on condition [duplicate]
...ble1.id = table2.id
You can also try this:
UPDATE table1
SET price=(SELECT price FROM table2 WHERE table1.id=table2.id);
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