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MySQL - SELECT WHERE field IN (subquery) - Extremely slow why?
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Rewrite the query into this
SELECT st1.*, st2.relevant_field FROM sometable st1
INNER JOIN sometable st2 ON (st1.relevant_field = st2.relevant_field)
GROUP BY st1.id /* list a unique sometable field here*/
HAVING COUNT(*) > 1
I think st2.relevant_...
How do I list all the columns in a table?
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For Oracle (PL/SQL)
SELECT column_name
FROM user_tab_cols
WHERE table_name = 'myTableName'
For MySQL
SHOW COLUMNS FROM table_name
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Is there any way to create a blank solution (.sln) file first and then add projects?
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Creating Solutions To create a new
solution
On the File menu, select New and then click Project.
In the Project types pane, select Other Project Types and
then select Visual Studio
Solutions.
In the Templates pane, select Blank Solution.
Enter a name for the project.
To chan...
Can I write a CSS selector selecting elements NOT having a certain class or attribute?
I would like to write a CSS selector rule that selects all elements that don't have a certain class. For example, given the following HTML:
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How to select the first element in the dropdown using jquery?
I want to know how to select the first option in all select tags on my page using jquery.
9 Answers
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SQL Server SELECT LAST N Rows
...d database... Now let us retrieve the Last 5 orders placed by Employee 5:
SELECT ORDERID, CUSTOMERID, OrderDate
FROM
(
SELECT ROW_NUMBER() OVER (PARTITION BY EmployeeID ORDER BY OrderDate DESC) AS OrderedDate,*
FROM Orders
) as ordlist
WHERE ordlist.EmployeeID = 5
AND ordlist.OrderedDate &...
Build an iOS app without owning a mac? [closed]
...r virtual machine (the name is unimportant, I called it "Mac"). In "Type", select "Mac OS X" and in "Version" select "macOS 10.13 High Sierra (64 bit)" (the Mac version you will install on the virtual machine is actually Catalina, but VirtualBox doesn't have that option yet and it works just fine if...
Convert Unix timestamp into human readable date using MySQL
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Use FROM_UNIXTIME():
SELECT
FROM_UNIXTIME(timestamp)
FROM
your_table;
See also: MySQL documentation on FROM_UNIXTIME().
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Use a list of values to select rows from a pandas dataframe [duplicate]
...andas.pydata.org/pandas-docs/stable/… for more details. A sort after the selection is needed.
– Wouter Overmeire
Aug 18 '14 at 15:16
1
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How to set OnClickListener on a RadioButton in Android?
...oGroup group, int checkedId) {
// checkedId is the RadioButton selected
}
});
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