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SQLite table constraint - unique on multiple columns
...Some other title');
sqlite> .mode col
sqlite> .headers on
sqlite> select * from t1;
id a b
---------- ---------- ----------------
1 Alice Some other title
2 Bob Palindromic guy
3 Charles chucky cheese
sq...
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 ...
LINQ equivalent of foreach for IEnumerable
...d evaluating Funcs
var evaluatedObservable = observable.ToEnumerable().Select(func => func()).ToList();
//Win
Assert.That(evaluatedObservable,
Is.EquivalentTo(values.ToList()));
}
The following fails with the error:
Expected: equivalent to < 0, 1, 2, 3, 4, 5, 6, 7, 8, ...
How to pass the -D System properties while testing on Eclipse?
...
Run -> Run configurations, select project, second tab: “Arguments”. Top box is for your program, bottom box is for VM arguments, e.g. -Dkey=value.
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Adding local .aar files to Gradle build using “flatDirs” is not working
... to why my next button is grayed out on the Create New Module dialog after selecting Import JAR/AAR Package?
– Kevin Crain
Nov 9 '16 at 8:50
1
...
Using varchar(MAX) vs TEXT on SQL Server
...es ('b')
insert into @table values ('c')
insert into @table values ('d')
select *
from @table
where a ='a'
This give an error:
The data types text and varchar are incompatible in the equal to operator.
Wheras this does not:
declare @table table (a varchar(max))
Interestingly, LIKE still wo...
Update a column value, replacing part of a string
...
Try using the REPLACE function:
mysql> SELECT REPLACE('www.mysql.com', 'w', 'Ww');
-> 'WwWwWw.mysql.com'
Note that it is case sensitive.
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C++ 读写xml方法整理（持续更新） - C/C++ - 清泛网 - 专注C/C++及内核技术
... VARIANT_TRUE; // validates during parsing
pDoc->setProperty(_bstr_t("SelectionNamespaces"), _variant_t(g_select_namespaces)); // set select namespaces
// associate xml and schema
pDoc->schemas = pSchema.GetInterfacePtr();
// load xml file
VARIANT_BOOL vbRet = pDoc->load...
jQuery find parent form
...
I would suggest using closest, which selects the closest matching parent element:
$('input[name="submitButton"]').closest("form");
Instead of filtering by the name, I would do this:
$('input[type=submit]').closest("form");
...
LINQ .Any VS .Exists - What's the difference?
... Enumerable.Repeat("ABCDEFGHIJKLMNOPQRSTUVWXYZ", 13)
.Select(s =>
{
var cryptoResult = new byte[4];
new RNGCryptoServiceProvider().GetBytes(cryptoResult);
return s[new Random(BitConverter.ToInt32(cryp...