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Django select only rows with duplicate field values
...ithout this, the subquery fails. The extra values tricks the ORM into only selecting the name column for the subquery.
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SQLAlchemy: print the actual query
...s:
print(str(statement))
This applies both to an ORM Query as well as any select() or other statement.
Note: the following detailed answer is being maintained on the sqlalchemy documentation.
To get the statement as compiled to a specific dialect or engine, if the statement itself is not already bo...
How do I enumerate through a JObject?
.... I.e. you ((IEnumerable<KeyValuePair<string, JToken>>)obj).Select(...) instead of plain-old obj.Select(...); or at least that's what I found it one part of my code.
– Adrian Ratnapala
Nov 26 '14 at 9:26
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How to check if a database exists in SQL Server?
...script:
DECLARE @dbname nvarchar(128)
SET @dbname = N'Senna'
IF (EXISTS (SELECT name
FROM master.dbo.sysdatabases
WHERE ('[' + name + ']' = @dbname
OR name = @dbname)))
-- code mine :)
PRINT 'db exists'
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Selecting the first “n” items with jQuery
With Jquery, I need to select just the first "n" items from the page, for example the first 20 links instead of selecting all of them with the usual
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PostgreSQL: How to pass parameters from command line?
...3="'2010-11-12'"
and then refer to the variables in sql as :v1, :v2 etc
select * from table_1 where id = :v1;
Please pay attention on how we pass string/date value using two quotes " '...' "
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Compare two files in Visual Studio
... the desktop. That's all!
Usage:
Open the Windows explorer via Win + E
Select two files to compare in the explorer
Drag and drop them as shown in the animation below:
After a few seconds (depending on the launch time of Visual Studio), the results will be shown in Visual Studio:
Note: It d...
How can I select all children of an element except the last child?
How would I select all but the last child using CSS3 selectors?
9 Answers
9
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SQL: deleting tables with prefix
...r you:
In the MySQL shell or through PHPMyAdmin, use the following query
SELECT CONCAT( 'DROP TABLE ', GROUP_CONCAT(table_name) , ';' )
AS statement FROM information_schema.tables
WHERE table_name LIKE 'myprefix_%';
This will generate a DROP statement which you can than copy and execut...
How to drop a PostgreSQL database if there are active connections to it?
...Query pg_stat_activity and get the pid values you want to kill, then issue SELECT pg_terminate_backend(pid int) to them.
PostgreSQL 9.2 and above:
SELECT pg_terminate_backend(pg_stat_activity.pid)
FROM pg_stat_activity
WHERE pg_stat_activity.datname = 'TARGET_DB' -- ← change this to your DB
AN...