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Oracle Differences between NVL and Coalesce
...n search contains comparison of nvl result with an indexed column.
create table tt(a, b) as
select level, mod(level,10)
from dual
connect by level<=1e4;
alter table tt add constraint ix_tt_a primary key(a);
create index ix_tt_b on tt(b);
explain plan for
select * from tt
where a=nvl(:1,a)
an...
psycopg2: insert multiple rows with one query
...("(%s,%s,%s,%s,%s,%s,%s,%s,%s)", x) for x in tup)
cur.execute("INSERT INTO table VALUES " + args_str)
and 2 minutes when using this method:
cur.executemany("INSERT INTO table VALUES(%s,%s,%s,%s,%s,%s,%s,%s,%s)", tup)
sh...
PadLeft function in T-SQL
I have the following table A:
17 Answers
17
...
How to check if object (variable) is defined in R?
...paces of attached packages, this would also fall short:
> exists("data.table")
[1] FALSE
require(data.table)
> exists("data.table", inherits = FALSE)
[1] FALSE
> exists("data.table")
[1] TRUE
The only thing I can think of to get around this -- to search in attached packages but not in ba...
How to work around the stricter Java 8 Javadoc when using Maven
...
Note that for the error no summary or caption for table, using <table summary=""> won't work anymore. If that's your situation, add a <caption> element to your table, like this:
<table>
<caption>Examples</caption>
...
</table>
H...
Tricks to manage the available memory in an R session
...
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...
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
share
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improve ...
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
...
'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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Getting result of dynamic SQL into a variable for sql-server
...
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...