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Difference between assertEquals and assertSame in phpunit?
...te objects match their attribute values in any case. So it's the method suitable for asserting object match.
$this->assertEquals($expected, $actual); PASSES
https://phpunit.de/manual/current/en/appendixes.assertions.html
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Tricks to manage the available memory in an R session
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I use the data.table package. With its := operator you can :
Add columns by reference
Modify subsets of existing columns by reference, and by group by reference
Delete columns by reference
None of these operations copy the (potentially...
'0000-00-00 00:00:00' can not be represented as java.sql.Timestamp error
I have a database table containing dates
12 Answers
12
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Difference between @OneToMany and @ElementCollection?
...ring> strings;
Simpler, isn't it? Note that you can still control the table and column names using @CollectionTable annotation.
See also:
Java Persistence/ElementCollection
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Getting result of dynamic SQL into a variable for sql-server
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dynamic version
ALTER PROCEDURE [dbo].[ReseedTableIdentityCol](@p_table varchar(max))-- RETURNS int
AS
BEGIN
-- Declare the return variable here
DECLARE @sqlCommand nvarchar(1000)
DECLARE @maxVal INT
set @sqlCommand = 'SELECT @maxVal...
When should I use mmap for file access?
...om. (The OS can detect which pages are unmodified by initially marking writable mmap'd pages as read only and catching seg faults, similar to Copy on Write strategy).
mmap is also useful for inter process communication. You can mmap a file as read / write in the processes that need to communica...
Why does MYSQL higher LIMIT offset slow the query down?
Scenario in short: A table with more than 16 million records [2GB in size]. The higher LIMIT offset with SELECT, the slower the query becomes, when using ORDER BY *primary_key*
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Position of least significant bit that is set
...how to squeeze some cycles out of it?" makes such an answer perfectly acceptable!
– Mehrdad Afshari
Apr 16 '09 at 17:08
5
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Select last N rows from MySQL
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You can do it with a sub-query:
SELECT * FROM (
SELECT * FROM table ORDER BY id DESC LIMIT 50
) sub
ORDER BY id ASC
This will select the last 50 rows from table, and then order them in ascending order.
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Fastest check if row exists in PostgreSQL
I have a bunch of rows that I need to insert into table, but these inserts are always done in batches. So I want to check if a single row from the batch exists in the table because then I know they all were inserted.
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