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How to generate a range of numbers between two numbers?
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Select non-persisted values with the VALUES keyword. Then use JOINs to generate lots and lots of combinations (can be extended to create hundreds of thousands of rows and beyond).
SELECT ones.n + 10*tens.n + 100*hundreds.n +...
Rails filtering array of objects by attribute value
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Try :
This is fine :
@logos = @attachments.select { |attachment| attachment.file_type == 'logo' }
@images = @attachments.select { |attachment| attachment.file_type == 'image' }
but for performance wise you don't need to iterate @attachments twice :
@logos , @images...
Stored procedure slow when called from web, fast from Management Studio
...ariables.
eg. change:
ALTER PROCEDURE [dbo].[sproc]
@param1 int,
AS
SELECT * FROM Table WHERE ID = @param1
to:
ALTER PROCEDURE [dbo].[sproc]
@param1 int,
AS
DECLARE @param1a int
SET @param1a = @param1
SELECT * FROM Table WHERE ID = @param1a
Seems strange, but it fixed my problem.
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Save PL/pgSQL output from PostgreSQL to a CSV file
...e or automate, you can use Postgresql's built in COPY command. e.g.
Copy (Select * From foo) To '/tmp/test.csv' With CSV DELIMITER ',' HEADER;
This approach runs entirely on the remote server - it can't write to your local PC. It also needs to be run as a Postgres "superuser" (normally called "ro...
How do I iterate through the alphabet?
In Python, could I simply ++ a char? What is an efficient way of doing this?
2 Answers
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How do I directly modify a Google Chrome Extension File? (.CRX)
... remove the _metadata folder.
From chrome://extensions in Developer mode select Load unpacked extension... and select your copied extension folder, if it contains a subfolder this is named by the version, select this version folder where there is a manifest file, this file is necessary for Chrome....
How do I show an open file in eclipse Package Explorer?
...oices. The choices will vary depending on what plugins you have installed. Select the option you want and press Enter.
The fastest way to select an option is to use the first letter of the option, eg. to go to the Package Explorer, press P (you may have to do this 2 or 3 times depending on how many...
“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...int, unique key (u));
mysql> insert into foo (u) values (10);
mysql> select * from foo;
+----+------+
| id | u |
+----+------+
| 1 | 10 |
+----+------+
mysql> show create table foo\G
CREATE TABLE `foo` (
`id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
`u` int(11) DEFAULT NULL,
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How does Duff's device work?
...nion that is the key to understanding this code.
– Richard Chambers
Apr 20 '13 at 23:03
3
Am I mi...
Select Row number in postgres
How to select row number in postgres.
1 Answer
1
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