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How to use the “required” attribute with a “radio” input field
...buttons they must all have the same name value. This allows only one to be selected at a time and applies required to the whole group.
<form>
Select Gender:<br>
<label>
<input type="radio" name="gender" value="male" required>
Male
</label><b...
postgres: upgrade a user to be a superuser?
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SELECT rolname, rolsuper FROM pg_roles; to @masterweily
– caulfield
May 30 '13 at 11:44
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How to select the row with the maximum value in each group
In a dataset with multiple observations for each subject I want to take a subset with only the maximum data value for each record. For example, with a following dataset:
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How can I exclude one word with grep?
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-v or --invert-match select non-matching lines. In your case grep -v 'unwanted_word' file or grep --invert-match 'unwanted_word' file.
– adamski.pro
Nov 29 '16 at 7:10
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Postgres NOT in array
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SELECT COUNT(*) FROM "messages" WHERE NOT (3 = ANY (recipient_ids))
You can always negate WHERE (condition) with WHERE NOT (condition)
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pandas dataframe columns scaling with sklearn
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@RajeshThevar The outer brackets are pandas' typical selector brackets, telling pandas to select a column from the dataframe. The inner brackets indicate a list. You're passing a list to the pandas selector. If you just use single brackets - with one column name followed by ...
In PHP, how do you change the key of an array element?
...y, you can change the key directly from the mysql statement:
instead of
"select ´id´ from ´tablename´..."
use something like:
"select ´id´ **as NEWNAME** from ´tablename´..."
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i...
What is the difference between Non-Repeatable Read and Phantom Read?
...e query have the same value before and after, but different rows are being selected (because B has deleted or inserted some). Example: select sum(x) from table; will return a different result even if none of the affected rows themselves have been updated, if rows have been added or deleted.
In ...
When do I need to use Begin / End Blocks and the Go keyword in SQL Server?
..., and IF statements, etc, where you need more then one step...
IF EXISTS (SELECT * FROM my_table WHERE id = @id)
BEGIN
INSERT INTO Log SELECT @id, 'deleted'
DELETE my_table WHERE id = @id
END
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Beautiful Soup and extracting a div and its contents by ID
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Beautiful Soup 4 supports most CSS selectors with the .select() method, therefore you can use an id selector such as:
soup.select('#articlebody')
If you need to specify the element's type, you can add a type selector before the id selector:
soup.select('di...