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jQuery: Select data attributes that aren't empty?
I'm trying to select all elements that have a data-go-to attribute that is not empty.
11 Answers
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Find method references in Xcode
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Select the method you're interested in, or position the text cursor within it.
Open the "Related Files" menu via the icon at the top-left of the Editor. (It's the button immediately to the left of the back button).
Go to the ...
How to check if field is null or empty in MySQL?
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Either use
SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1
from tablename
or
SELECT case when field1 IS NULL or field1 = ''
then 'empty'
else field1
end as field1
from tablename
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XPath to select Element by attribute value
...he parts in [ ]) shouldn't have slashes immediately before them. Also, to select the Employee element itself, you should leave off the /text() at the end or otherwise you'd just be selecting the whitespace text values immediately under the Employee element.
//Employee[@id='4']
Edit: As Jens poin...
Finding duplicate values in MySQL
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Do a SELECT with a GROUP BY clause. Let's say name is the column you want to find duplicates in:
SELECT name, COUNT(*) c FROM table GROUP BY name HAVING c > 1;
This will return a result with the name value in the first colum...
Troubleshooting “Illegal mix of collations” error in mysql
Am getting the below error when trying to do a select through a stored procedure in MySQL.
16 Answers
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Select a Dictionary with LINQ
I have used the "select" keyword and extension method to return an IEnumerable<T> with LINQ, but I have a need to return a generic Dictionary<T1, T2> and can't figure it out. The example I learned this from used something in a form similar to the following:
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Insert results of a stored procedure into a temporary table
How do I do a SELECT * INTO [temp table] FROM [stored procedure] ? Not FROM [Table] and without defining [temp table] ?
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Retrieve the maximum length of a VARCHAR column in SQL Server
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Use the built-in functions for length and max on the description column:
SELECT MAX(LEN(DESC)) FROM table_name;
Note that if your table is very large, there can be performance issues.
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MySQL IF NOT NULL, then display 1, else display 0
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SELECT c.name, IF(a.addressid IS NULL,0,1) AS addressexists
FROM customers c
LEFT JOIN addresses a ON c.customerid = a.customerid
WHERE customerid = 123
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