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Rails 3: Get Random Record
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Thing.first(:order => "RANDOM()") # For MySQL :order => "RAND()", - thanx, @DanSingerman
# Rails 3
Thing.order("RANDOM()").first
or
Thing.first(:offset => rand(Thing.count))
# Rails 3
Thing.offset(rand(Thing.count)).first
Actually, in Rails 3 all example...
When and why are database joins expensive?
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MySQL, Oracle, SQL Server, Sybase, postgreSQL,etc. care not the order of joins. I've worked with DB2 and it also, to my knowledge, doesn't care what order you put them in. This is not helpful advice in the general case
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TINYTEXT, TEXT, MEDIUMTEXT, and LONGTEXT maximum storage sizes
Per the MySQL docs , there are four TEXT types:
4 Answers
4
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How to select records from last 24 hours using SQL?
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In MySQL:
SELECT *
FROM mytable
WHERE record_date >= NOW() - INTERVAL 1 DAY
In SQL Server:
SELECT *
FROM mytable
WHERE record_date >= DATEADD(day, -1, GETDATE())
In Oracle:
SELECT *
FROM mytable
WHER...
How to delete duplicates on a MySQL table?
I need to DELETE duplicated rows for specified sid on a MySQL table.
25 Answers
25...
Mysql: Select rows from a table that are not in another
... this only works as expected when none of the columns have NULL values. In MySQL NULL != NULL so every row that has a NULL value will be returned even if there is a duplicate row in the second table.
– Kyle Kochis
Apr 7 '15 at 2:49
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Generate GUID in MySQL for existing Data?
I've just imported a bunch of data to a MySQL table and I have a column "GUID" that I want to basically fill down all existing rows with new and unique random GUID's.
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Is there a way to do method overloading in TypeScript?
...ally achieve the same thing with optional, or default parameters - or with union types, or with a bit of object-orientation.
The Actual Question
The actual question asks for an overload of:
someMethod(stringParameter: string): void {
someMethod(numberParameter: number, stringParameter: string): ...
What scalability problems have you encountered using a NoSQL data store? [closed]
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I've switched a small subproject from MySQL to CouchDB, to be able to handle the load. The result was amazing.
About 2 years ago, we've released a self written software on http://www.ubuntuusers.de/ (which is probably the biggest German Linux community website)....
MySQL Cannot Add Foreign Key Constraint
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lol same. MySQL could use more precise error handling on this kind of stuff.
– dave
Apr 17 at 23:38
add a comm...