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SQL Server insert if not exists best practice
...sert Competitors where doesn't already exist":
INSERT Competitors (cName)
SELECT DISTINCT Name
FROM CompResults cr
WHERE
NOT EXISTS (SELECT * FROM Competitors c
WHERE cr.Name = c.cName)
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Check if a temporary table exists and delete if it exists before creating a temporary table
...me in SQL Server 2005, with the extra "foo" column appearing in the second select result:
IF OBJECT_ID('tempdb..#Results') IS NOT NULL DROP TABLE #Results
GO
CREATE TABLE #Results ( Company CHAR(3), StepId TINYINT, FieldId TINYINT )
GO
select company, stepid, fieldid from #Results
GO
ALTER TABLE #R...
How to concatenate strings of a string field in a PostgreSQL 'group by' query?
...at the question asked for, even letting you specify the delimiter string:
SELECT company_id, string_agg(employee, ', ')
FROM mytable
GROUP BY company_id;
Postgres 9.0 also added the ability to specify an ORDER BY clause in any aggregate expression; otherwise, the order is undefined. So you can no...
Why is the apt-get function not working in the terminal on Mac OS X v10.9 (Mavericks)?
...ollowing in your Mac OS X terminal:
/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
After that, usage of Homebrew is brew install <package>.
One of the prerequisites for Homebrew are the XCode command line tools.
Install XCode from the App ...
What is the best way to auto-generate INSERT statements for a SQL Server table?
...2008:
Right-click on the database and go to Tasks > Generate Scripts.
Select the tables (or objects) that you want to generate the script against.
Go to Set scripting options tab and click on the Advanced button.
In the General category, go to Type of data to script
There are 3 options: Schema ...
How to have a default option in Angular.js select box
...
You can simply use ng-init like this
<select ng-init="somethingHere = options[0]"
ng-model="somethingHere"
ng-options="option.name for option in options">
</select>
...
Search text in stored procedure in SQL Server
...t the schema name by adding SCHEMA_NAME(o.schema_id) AS Schema_Name to the select clause.
– patricus
Jul 7 '16 at 15:07
6
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NOT IN vs NOT EXISTS
...llow NULLs the NOT IN will be treated identically to the following query.
SELECT ProductID,
ProductName
FROM Products p
WHERE NOT EXISTS (SELECT *
FROM [Order Details] od
WHERE p.ProductId = od.ProductId)
The exact plan may vary but for my examp...
How to safely open/close files in python 2.4
...name)
print txt.read()
txt.close()
print "Change the file name"
file_again=raw_input('>')
print "New file name %r" %(file_again)
txt_again=open(file_again)
print txt_again.read()
txt_again.close()
It's necessary to how many times you opened file have to close that times.
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Fastest way to determine if record exists
...
SELECT TOP 1 products.id FROM products WHERE products.id = ?; will outperform all of your suggestions as it will terminate execution after it finds the first record.
...