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Difference between a theta join, equijoin and natural join
...ed SQL query would be like this (you can play with all the examples here)
SELECT *
FROM Product
JOIN Component
ON Product.Pname = Component.Pname
and the result:
| PNAME | PRICE | CNAME | COST |
----------------------------------
| Laptop | 1500 | CPU | 500 |
| Laptop | 1500 | hdd ...
How to do multiple line editing?
...
Press alt + shift + A to Toggle block selection (Toggle block / column selection in the current text editor), this will let you write vertically in eclipse, then you can easily do this.
Go to Window->Preferences.
Find for binding in text box surrounded b...
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...
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?
...
How to avoid warning when introducing NAs by coercion
...t know how to avoid getting a warning when using as.numeric to convert a character vector.
4 Answers
...
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 ...
How to use count and group by at the same select statement
I have an sql select query that has a group by.
I want to count all the records after the group by statement.
Is there a way for this directly from sql?
For example, having a table with users I want to select the different towns and the total number of users
...
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:
...
How to select unique records by SQL
When I perform "SELECT * FROM table" I got results like below:
8 Answers
8
...
How to exclude particular class name in CSS selector?
...
One way is to use the multiple class selector (no space as that is the descendant selector):
.reMode_hover:not(.reMode_selected):hover
{
background-color: #f0ac00;
}
<a href="" title="Design" class="reMode_design reMode_hover">
<span&...