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SQL JOIN vs IN performance?
...king, IN and JOIN are different queries that can yield different results.
SELECT a.*
FROM a
JOIN b
ON a.col = b.col
is not the same as
SELECT a.*
FROM a
WHERE col IN
(
SELECT col
FROM b
)
, unless b.col is unique.
However, this is the syno...
Query to list all stored procedures
...e not in the master database, system stored procedures won't be returned.
SELECT *
FROM DatabaseName.INFORMATION_SCHEMA.ROUTINES
WHERE ROUTINE_TYPE = 'PROCEDURE'
If for some reason you had non-system stored procedures in the master database, you could use the query (this will filter out MOST ...
How does the static modifier affect this code?
...type double, the
default value is positive zero, that is, 0.0d. For type char, the
default value is the null character, that is, '\u0000'. For type
boolean, the default value is false. For all reference types (§4.3),
the default value is null.
...
Find method references in Xcode
...
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 ...
Unicode characters in URLs
In 2010, would you serve URLs containing UTF-8 characters in a large web portal?
7 Answers
...
Get selected option text with JavaScript
...
Try options
function myNewFunction(sel) {
alert(sel.options[sel.selectedIndex].text);
}
<select id="box1" onChange="myNewFunction(this);">
<option value="98">dog</option>
<option value="7122">cat</option>
<option value="142">bird</option&g...
Regex Email validation
...he new TLD's that are being issued, as you can have TLD's with more than 3 characters now.
– AaronLS
Jul 22 '13 at 19:04
...
How to check if field is null or empty in MySQL?
...
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
...
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:
...
Set selected index of an Android RadioGroup
Is there a way to set the selected index of a RadioGroup in android, other than looping through the child radiobuttons and selecting checking the radio button at the selected index?
...