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PadLeft function in T-SQL
I have the following table A:
17 Answers
17
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Is floating-point math consistent in C#? Can it be?
...types uint and ulong.
As suggested in another answer, you can use lookup tables, where each element in the table is a binary fixed point number, to help implement complex functions such as sine, cosine, square root, and so on. If the lookup table is less granular than the fixed point number, it is...
Permanently Set Postgresql Schema Path
... set schema path in Postgres so that I don't every time specify schema dot table e.g. schema2.table .
Set schema path:
3 ...
What is the difference between memoization and dynamic programming?
...g all related sub-problems first, typically by filling up an n-dimensional table. Based on the results in the table, the solution to the "top" / original problem is then computed.
If you use memoization to solve the problem you do it by maintaining a map of already solved sub problems. You do it "t...
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...
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
...
Decompressing GZip Stream from HTTPClient Response
...w HttpClient();
HttpResponseMessage response;
DataSet dsTable = new DataSet();
try
{
//Gets the headers that should be sent with each request
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"))...
'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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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...