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How to check for Is not Null And Is not Empty string in SQL server?
... ('A'),
(''),
(' '),
(NULL);
SELECT *
FROM T
WHERE C <> ''
Returns just the single row A. I.e. The rows with NULL or an empty string or a string consisting entirely of spaces are all excluded by this query.
SQL Fiddle
...
LINQ query on a DataTable
...w in myDataTable.AsEnumerable()
where myRow.Field<int>("RowNo") == 1
select myRow;
And as @Keith says, you'll need to add a reference to System.Data.DataSetExtensions
AsEnumerable() returns IEnumerable<DataRow>. If you need to convert IEnumerable<DataRow> to a DataTable, use the...
How do you display code snippets in MS Word preserving format and syntax highlighting?
...d install Notepad++ and do the following:
Paste your code in the window;
Select the programming language from the language menu;
Select the text to copy;
Right click and select Plugin commands -> Copy Text with Syntax Highlighting;
Paste it into MS Word and you are good to go!
Update 29/06/20...
How to convert std::string to LPCWSTR in C++ (Unicode)
... int len;
int slength = (int)s.length() + 1;
len = MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, 0, 0);
wchar_t* buf = new wchar_t[len];
MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, buf, len);
std::wstring r(buf);
delete[] buf;
return r;
}
std::wstring stemp...
Best implementation for hashCode method for a collection
...he field f is a boolean:
calculate (f ? 0 : 1);
If the field f is a byte, char, short or int: calculate (int)f;
If the field f is a long: calculate (int)(f ^ (f >>> 32));
If the field f is a float: calculate Float.floatToIntBits(f);
If the field f is a double: calculate Double.doubleToLong...
android button selector
This is a button selector such that when normal it appears red, when pressed it appears grey.
6 Answers
...
Set custom HTML5 required field validation message
...he HTML5 "required" functionality to also validate against only whitespace chars being submitted (whereas by default it only validates against an empty string being submitted). So I changed the two lines with if (input.value == "") {, to instead read if (input.value.trim() == "") { - does the trick ...
jQuery $(“#radioButton”).change(…) not firing during de-selection
...Andomar's solution worked but this makes more sense to me. Using the class selector prevents having to change the function if the form changes or has a dynamic number of fields. Yay for necro votes! (though now 2 years later jQuery recommends using prop() instead of attr(). api.jquery.com/prop)
...
fatal error: malformed or corrupted AST file - Xcode
...olved the issue for me. In Xcode, go to Window->Organizer->Projects, select your project, and press the "Delete..." button next to "Derived data".
If this doesn't work, you can try to do a Product->Clean (Cmd+Shift+k).
...
How do MySQL indexes work?
...be faster to go through the pages one by one (in a database, this is "poor selectivity").
For a 10-page book, it makes no sense to make an index, as you may end up with a 10-page book prefixed by a 5-page index, which is just silly - just scan the 10 pages and be done with it.
The index also needs t...