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What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...'t, then use DISTINCT.
GROUP BY in MySQL sorts results. You can even do:
SELECT u.profession FROM users u GROUP BY u.profession DESC
and get your professions sorted in DESC order.
DISTINCT creates a temporary table and uses it for storing duplicates. GROUP BY does the same, but sortes the disti...
How to select rows that have current day's timestamp?
I am trying to select only today's records from a database table.
9 Answers
9
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How and why does 'a'['toUpperCase']() in JavaScript work?
... same as anyObject.anyPropertyName when anyPropertyName hasn't problematic characters.
See Working with Objects, from the MDN.
The toUpperCase method is attached to the type String. When you call a function on a primitive value, here 'a', it is automatically promoted to an object, here a String :
...
How to convert a column number (e.g. 127) into an Excel column (e.g. AA)
... {
modulo = (dividend - 1) % 26;
columnName = Convert.ToChar(65 + modulo).ToString() + columnName;
dividend = (int)((dividend - modulo) / 26);
}
return columnName;
}
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Select statement to find duplicates on certain fields
...get the list of fields for which there are multiple records, you can use..
select field1,field2,field3, count(*)
from table_name
group by field1,field2,field3
having count(*) > 1
Check this link for more information on how to delete the rows.
http://support.microsoft.com/kb/139444
There sh...
What are the downsides to using Dependency Injection? [closed]
...inject - the text "Hello World". Easy enough...
void Say_Something (const char *p_text)
{
std::cout << p_text << std::endl;
}
How is that more inflexible than the original? Well, what if I decide that the output should be unicode. I probably want to switch from std::cout to std::wco...
How do I toggle an element's class in pure JavaScript?
...e seperators. for example it doesn't work if class name contain dash ("-") char: btn, btn-red will both match'\\b' + 'btn' + '\\b' !!
– S.Serpooshan
Feb 5 '19 at 6:47
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SQL DROP TABLE foreign key constraint
...your table, you could use this SQL (if you're on SQL Server 2005 and up):
SELECT *
FROM sys.foreign_keys
WHERE referenced_object_id = object_id('Student')
and if there are any, with this statement here, you could create SQL statements to actually drop those FK relations:
SELECT
'ALTER TABL...
How does deriving work in Haskell?
...> "parm"
where toL (x:y) = (toLower x):y
unCapalize :: [Char] -> [Char]
unCapalize (x:y) = (toLower x):y
And some borrowed helper code taken from Syb III / replib 0.2.
typeInfo :: DecQ -> Q (Name, [Name], [(Name, Int)], [(Name, [(Maybe Name, Type)])])
typeInfo m =
...
Search text in stored procedure in SQL Server
...t the schema name by adding SCHEMA_NAME(o.schema_id) AS Schema_Name to the select clause.
– patricus
Jul 7 '16 at 15:07
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