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Is there a difference between copy initialization and direct initialization?
...ain function :
int main()
{
A a1 = 1; // OK: copy-initialization selects A::A(int)
A a2(2); // OK: direct-initialization selects A::A(int)
A a3 {4, 5}; // OK: direct-list-initialization selects A::A(int, int)
A a4 = {4, 5}; // OK: copy-list-initialization selects A::A(i...
Convert INT to VARCHAR SQL
I am using Sybase and I am doing a select which returns me a column called "iftype", but its type is int and I need to convert into varchar. When I try to do the select without the convert function I get this error:
...
How to reshape data from long to wide format
...mes(df) <- unique(dat1$name)
df
sqldf package:
library(sqldf)
sqldf('SELECT name,
MAX(CASE WHEN numbers = 1 THEN value ELSE NULL END) x1,
MAX(CASE WHEN numbers = 2 THEN value ELSE NULL END) x2,
MAX(CASE WHEN numbers = 3 THEN value ELSE NULL END) x3,
MAX(CASE WHEN numbe...
How to randomly select rows in SQL?
...
SELECT TOP 5 Id, Name FROM customerNames
ORDER BY NEWID()
That said, everybody seems to come to this page for the more general answer to your question:
Selecting a random row in SQL
Select a random row with MySQL:
SELECT...
How to get the first and last date of the current year?
...
SELECT
DATEADD(yy, DATEDIFF(yy, 0, GETDATE()), 0) AS StartOfYear,
DATEADD(yy, DATEDIFF(yy, 0, GETDATE()) + 1, -1) AS EndOfYear
The above query gives a datetime value for midnight at the beginning of December 31. This ...
How do we count rows using older versions of Hibernate (~2009)?
...eturn int and use this form:
int count = ((Long)getSession().createQuery("select count(*) from Book").uniqueResult()).intValue();
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How do you view ALL text from an ntext or nvarchar(max) in SSMS?
...tions on the Query menu, or right-click in the SQL Server Query window and select Query Options.
...
Maximum Characters Retrieved
Enter a number from 1 through 65535 to specify the maximum number of characters that will be displayed in each cell.
Maximum is, as you see, 64k. T...
SQL query for today's date minus two months
I want to select all the records in a table where their date of entry is older then 2 months.
5 Answers
...
How do you convert a DataTable into a generic list?
...ataTable
//using lamdaexpression
emp = (from DataRow row in dt.Rows
select new Employee
{
_FirstName = row["FirstName"].ToString(),
_LastName = row["Last_Name"].ToString()
}).ToList();
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How do I specify a pointer to an overloaded function?
...putIterator, InputIterator, UnaryFunction );
Template deduction needs to select a type for UnaryFunction at the point of the call. But f doesn't have a specific type - it's an overloaded function, there are many fs each with different types. There is no current way for for_each to aid the template...