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When to use Vanilla JavaScript vs. jQuery?
...now)
this.value (on most input types. only issues I know are IE when a <select> doesn't have value properties set on its <option> elements, or radio inputs in Safari.)
this.className to get or set an entire "class" property
this.selectedIndex against a <select> to get the selected ...
What's the difference between disabled=“disabled” and readonly=“readonly” for HTML form input fields
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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 ...
How to select the rows with maximum values in each group with dplyr? [duplicate]
I would like to select a row with maximum value in each group with dplyr.
6 Answers
6
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How to get nth jQuery element
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Why not browse the (short) selectors page first?
Here it is: the :eq() operator. It is used just like get(), but it returns the jQuery object.
Or you can use .eq() function too.
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Postgresql - unable to drop database because of some auto connections to DB
...n psql)
You can then terminate all connections to this db except your own:
SELECT pid, pg_terminate_backend(pid)
FROM pg_stat_activity
WHERE datname = current_database() AND pid <> pg_backend_pid();
On older versions pid was called procpid so you'll have to deal with that.
Since you've revo...
How to get a group of toggle buttons to act like radio buttons in WPF?
...ike toggle buttons, but also as radio buttons where only one button can be selected / pressed down at a current time. It also need to have a state where none of the buttons are selected / pressed down.
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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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Show constraints on tables command
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Simply query the INFORMATION_SCHEMA:
USE INFORMATION_SCHEMA;
SELECT TABLE_NAME,
COLUMN_NAME,
CONSTRAINT_NAME,
REFERENCED_TABLE_NAME,
REFERENCED_COLUMN_NAME
FROM KEY_COLUMN_USAGE
WHERE TABLE_SCHEMA = "<your_database_name>"
AND TABLE_NAME = "<y...
MySQL table is marked as crashed and last (automatic?) repair failed
... This was a quick fix! Had a "bad" options table. Make sure that you select the correct database first !
– jyllstuart
Jan 10 '19 at 15:54
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jQuery: checking if the value of a field is null (empty)
... be null, it's always a string value. this isn't entirely true. I've got a select containing no options. When I perform .val() on this it returns null. Jquery 1.7.2
– Liam
Jan 14 '13 at 11:07
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