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Change type of varchar field to integer: “cannot be cast automatically to type integer”
...YPE integer USING (trim(col_name)::integer);
to strip white space before converting.
This shoud've been obvious from an error message if the command was run in psql, but it's possible PgAdmin-III isn't showing you the full error. Here's what happens if I test it in psql on PostgreSQL 9.2:
=> ...
Can virtual functions have default parameters?
.... However since no one mentions simple and effective solution, here it is: Convert your parameters to struct and then you can have default values to struct members!
So instead of,
//bad idea
virtual method1(int x = 0, int y = 0, int z = 0)
do this,
//good idea
struct Param1 {
int x = 0, y = 0...
How do I provide custom cast support for my class?
... implicit operator byte[] (MyType x)
{
byte[] ba = // put code here to convert x into a byte[]
return ba;
}
or
public static explicit operator MyType(byte[] x)
{
if (!CanConvert)
throw new DataValueNullException();
// Factory to convert byte[] x into MyType
MyType mt ...
I want to get Year, Month, Day, etc from Java Date to compare with Gregorian Calendar date in Java.
...
With Java 8 and later, you can convert the Date object to a LocalDate object and then easily get the year, month and day.
Date date = new Date();
LocalDate localDate = date.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();
int year = localDate.ge...
T-SQL get SELECTed value of stored procedure
... for INTs, because RETURN can only return a single int value and nulls are converted to a zero.
OUTPUT PARAMETER
you can use an output parameter:
CREATE PROCEDURE GetMyInt
( @Param int
,@OutValue int OUTPUT)
AS
SELECT @OutValue=MyIntField FROM MyTable WHERE MyPrimaryKeyField = @Param
RETURN ...
int to hex string
I need to convert an int to hex string.
4 Answers
4
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Finding the number of days between two dates
...
Convert your dates to unix timestamps, then substract one from the another. That will give you the difference in seconds, which you divide by 86400 (amount of seconds in a day) to give you an approximate amount of days in tha...
Jquery Ajax Posting json to webservice
...uses (JavaScriptSerializer) is pretty flexible, and will do what it can to convert your input data into the server-side type you specify.
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What do the following phrases mean in C++: zero-, default- and value-initialization?
... if T is a scalar type (3.9), the object is set to the value of 0 (zero) converted to T;
— if T is a non-union class type, each nonstatic data member and each base-class subobject is zero-initialized;
— if T is a union type, the object’s first named data member is zero-initialized;
— i...
How do I initialize an empty array in C#?
...
string[] a = { };
[The elements inside the bracket should be implicitly convertible to type defined, for instance, string[] a = { "a", "b" };]
Or yet another:
var a = Enumerable.Empty<string>().ToArray();
Here is a more declarative way:
public static class Array<T>
{
public s...