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How do I create a unique constraint that also allows nulls?
...dy found separately in other, properly defined columns. It should never be selected or used.
So, my story is that this is not a surrogate NULL, and I'm sticking to it! Since we don't actually want the non-NULL value for any purpose other than to trick the UNIQUE index to ignore NULLs, our use case ...
How to write a Unit Test?
...l,calculatedVal).
Test your method by running it (in Eclipse, right click, select Run as → JUnit test).
//for normal addition
@Test
public void testAdd1Plus1()
{
int x = 1 ; int y = 1;
assertEquals(2, myClass.add(x,y));
}
Add other cases as desired.
Test that your binary sum doe...
Why use the params keyword?
...
You could also use return args.Select(x => x + 2).Sum();
– bbvg
Aug 22 '17 at 21:07
...
How do I specify “close existing connections” in sql script
...RE @isStatAsyncOn bit
DECLARE @jobId int
DECLARE @sqlString nvarchar(500)
SELECT @dbId = database_id,
@isStatAsyncOn = is_auto_update_stats_async_on
FROM sys.databases
WHERE name = 'db_name'
IF @isStatAsyncOn = 1
BEGIN
ALTER DATABASE [db_name] SET AUTO_UPDATE_STATISTICS_ASYNC OFF
...
How to pass table value parameters to stored procedure from .net code
...;T, TProperty>(this IEnumerable<T> list, Func<T, TProperty> selector)
{
var tbl = new DataTable();
tbl.Columns.Add("Id", typeof(T));
foreach (var item in list)
{
tbl.Rows.Add(selector.Invoke(item));
}
return tbl;
...
Separate Back Stack for each tab in Android using Fragments
...t(tabId).size() == 0){
/*
* First time this tab is selected. So add first fragment of that tab.
* Dont need animation, so that argument is false.
* We are adding a new fragment which is not present in stack. So add to stack is true.
*/
...
How to store arrays in MySQL?
... retrieve a person and all of their fruit you can do something like this:
SELECT p.*, f.*
FROM person p
INNER JOIN person_fruit pf
ON pf.person_id = p.id
INNER JOIN fruits f
ON f.fruit_name = pf.fruit_name
share
|...
How to speed up insertion performance in PostgreSQL
...rypto module) is (a lot) faster than uuid_generate_v4()
=# explain analyze select uuid_generate_v4(),* from generate_series(1,10000);
QUERY PLAN
---------------------------------------------------------------------------------------------------...
Best way to store time (hh:mm) in a database
...t a glance and performing calculations on them are straightforward.
E.g.
SELECT DATEDIFF(MINUTE, event_start, event_end)
ISO8601 date standard
If using SQLite then you don't have this, so instead use a Text field and store it in ISO8601 format eg.
"2013-01-27T12:30:00+0000"
Notes:
This use...
In Intellij, how do I toggle between camel case and underscore spaced?
...g Manipulation which has the capabilities you're looking for (and more).
Select historyOfPresentIllness and press Alt+M to bring up the plugin menu, then press:
5 - To snake_case (or to camelCase) which converts to history_of_present_illness
6 - To hyphen-case (or to snake_case) which converts...