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Kill a postgresql session/connection
...user to use this function. This works on all operating systems the same.
SELECT
pg_terminate_backend(pid)
FROM
pg_stat_activity
WHERE
-- don't kill my own connection!
pid <> pg_backend_pid()
-- don't kill the connections to other databases
AND datname = 'database...
No compiler is provided in this environment. Perhaps you are running on a JRE rather than a JDK?
...and check your installed JREs. You should have an entry with a JDK there.
Select the Execution Env as show below. Click OK
Then Right-Click on your Project -> Maven -> Update Project
Additionally, you may have to change Maven JRE (see @jlars62 answer) which is as follows. Goto Run -> Ru...
Copy/duplicate database without using mysqldump
...the references, you can run the following to copy the data:
INSERT INTO x SELECT * FROM other_db.y;
If you're using MyISAM, you're better off to copy the table files; it'll be much faster. You should be able to do the same if you're using INNODB with per table table spaces.
If you do end up doin...
selecting unique values from a column
...
Use the DISTINCT operator in MySQL:
SELECT DISTINCT(Date) AS Date FROM buy ORDER BY Date DESC;
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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...
Insert Data Into Temp Table with Query
...
SELECT *
INTO #Temp
FROM
(SELECT
Received,
Total,
Answer,
(CASE WHEN application LIKE '%STUFF%' THEN 'MORESTUFF' END) AS application
FROM
FirstTable
WHERE
Recieved = 1 AND
applicati...
SQL: How to properly check if a record exists
...
It's better to use either of the following:
-- Method 1.
SELECT 1
FROM table_name
WHERE unique_key = value;
-- Method 2.
SELECT COUNT(1)
FROM table_name
WHERE unique_key = value;
The first alternative should give you no result or one result, the second count should be zero or on...
Open two instances of a file in a single Visual Studio session
...
Here's how to do it...
Select the tab you want two copies of
Select menu Window → New Window from the menu.
Right click the new tab and select New Vertical Tab Group
If New Window is not listed in the *Window menu note that the command does exi...
SQL - using alias in Group By
... following order:
FROM clause
WHERE clause
GROUP BY clause
HAVING clause
SELECT clause
ORDER BY clause
For most relational database systems, this order explains which names (columns or aliases) are valid because they must have been introduced in a previous step.
So in Oracle and SQL Server, you...
How to remove all namespaces from XML with C#?
... return new XElement(xmlDocument.Name.LocalName, xmlDocument.Elements().Select(el => RemoveAllNamespaces(el)));
}
It's working 100%, but I have not tested it much so it may not cover some special cases... But it is good base to start.
...