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How can I get column names from a table in SQL Server?
... much more by querying the Information Schema views.
This sample query:
SELECT *
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = N'Customers'
Can be made over all these DB objects:
CHECK_CONSTRAINTS
COLUMN_DOMAIN_USAGE
COLUMN_PRIVILEGES
COLUMNS
CONSTRAINT_COLUMN_USAGE
CONSTRAINT_...
How to select a CRAN mirror in R
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Repository selection screen cannot be shown on your system (OS X), since OS X no longer includes X11. R tries to show you the prompt through X11. Install X11 from http://xquartz.macosforge.org/landing/. Then run the install command. The...
Error when trying to obtain a certificate: The specified item could not be found in the keychain
...
I solved it. Ensure you are in the "Certificates" section and you select "Apple Worldwide Developer Relations Certification Authority" before requesting a certificate.
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Set selected item of spinner programmatically
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Use the following:
spinnerObject.setSelection(INDEX_OF_CATEGORY2).
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How do you beta test an iphone app?
...file
Start the Mac OS utility program Keychain Access.
In its main menu, select Keychain Access / Certificate Assistant / Request a Certificate From a Certificate Authority...
The dialog that pops up should aready have your email and name it it.
Select the radio button Saved to disk and Continue....
Using IQueryable with Linq
...ram. Your program then filters the data. In essence, the database does a SELECT * FROM Products, and returns EVERY product to you.
With the right IQueryable<T> provider, on the other hand, you can do:
IQueryable<Product> products = myORM.GetQueryableProducts();
var productsOver25 =...
How to map and remove nil values in Ruby
...blem:
N = 1_00_000
enum = 1.upto(1_000)
Benchmark.bmbm do |x|
x.report("select + map") { N.times { enum.select { |i| i.even? }.map{|i| i + 1} } }
x.report("map + compact") { N.times { enum.map { |i| i + 1 if i.even? }.compact } }
x.report("filter_map") { N.times { enum.filter_map { |i| i ...
Sublime - delete all lines containing specific value
...e got stuck for several minutes when I did Ctrl+Shift+K with 200,000 lines selected.
– Przemek D
Aug 28 '17 at 11:43
I...
Formatting Numbers by padding with leading zeros in SQL Server
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Change the number 6 to whatever your total length needs to be:
SELECT REPLICATE('0',6-LEN(EmployeeId)) + EmployeeId
If the column is an INT, you can use RTRIM to implicitly convert it to a VARCHAR
SELECT REPLICATE('0',6-LEN(RTRIM(EmployeeId))) + RTRIM(EmployeeId)
And the code to re...
How to get the number of days of difference between two dates on mysql?
...lues are
used in the calculation
In your case, you'd use :
mysql> select datediff('2010-04-15', '2010-04-12');
+--------------------------------------+
| datediff('2010-04-15', '2010-04-12') |
+--------------------------------------+
| 3 |
+--------------...