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What are the uses for Cross Join?
...ly, like size and color information for a particular article of clothing:
select
size,
color
from
sizes CROSS JOIN colors
Maybe you want a table that contains a row for every minute in the day, and you want to use it to verify that a procedure has executed each minute, so you might c...
Switch case with fallthrough?
...
Or in this simple case a character class [23])
– SiegeX
Apr 6 '11 at 6:50
4
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How can I find out what FOREIGN KEY constraint references a table in SQL Server?
...
Here it is:
SELECT
OBJECT_NAME(f.parent_object_id) TableName,
COL_NAME(fc.parent_object_id,fc.parent_column_id) ColName
FROM
sys.foreign_keys AS f
INNER JOIN
sys.foreign_key_columns AS fc
ON f.OBJECT_ID = fc.constra...
What is the string concatenation operator in Oracle?
...
It is ||, for example:
select 'Mr ' || ename from emp;
The only "interesting" feature I can think of is that 'x' || null returns 'x', not null as you might perhaps expect.
...
Moving Files into a Real Folder in Xcode
... Xcode should now be red (that's OK!).
From the Identity and Type manager, select the Group in Xcode that you want to relocate, then click the folder icon from the info pane:
In the Finder selection dialog, locate the equivalent new folder you created for this group in step 2. All the files insid...
Find the host name and port using PSQL commands
...
SELECT *
FROM pg_settings
WHERE name = 'port';
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T-SQL stored procedure that accepts multiple Id values
...nguages only.
XML. Very good for inserting many rows; may be overkill for SELECTs.
Table of Numbers. Higher performance/complexity than simple iterative method.
Fixed-length Elements. Fixed length improves speed over the delimited string
Function of Numbers. Variations of Table of Numbers and fixed...
foreach with index [duplicate]
...
You can do the following
foreach (var it in someCollection.Select((x, i) => new { Value = x, Index = i }) )
{
if (it.Index > SomeNumber) //
}
This will create an anonymous type value for every entry in the collection. It will have two properties
Value: with the ori...
How can I change the file type association of an existing file in WebStorm?
...t patterns by which a file gets associated as some type or other.
If you select the patterns for a file type you have wrongly selected (in your case Text type) you can remove the filename pattern with which was created to associate you file's filename as a wrong type.
Then click Apply > OK
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MySQL indexes - what are the best practices?
...t them. Generally I put an index on any fields that I will be searching or selecting using a WHERE clause but sometimes it doesn't seem so black and white.
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