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SQL WHERE condition is not equal to?
... clause may be negated according to the above rules. The negation of this
select *
from foo
where test-1
and test-2
and ( test-3
OR test-4
)
is
select *
from foo
where NOT( test-1
and test-2
and ( test-3
OR te...
How do I use cascade delete with SQL Server?
...elete" to an existing foreign key in SQL Server Management Studio:
First, select your Foreign Key, and open it's "DROP and Create To.." in a new Query window.
Then, just add ON DELETE CASCADE to the ADD CONSTRAINT command:
And hit the "Execute" button to run this query.
By the way, to get a l...
Android: How to bind spinner to custom object list?
... has its own ID (the IDs are not equal to display sequence). When the user selects the name from the list the variable currentID has to be changed.
...
Is there a MySQL option/feature to track history of changes to records?
...i AFTER INSERT ON MyDB.data FOR EACH ROW
INSERT INTO MyDB.data_history SELECT 'insert', NULL, NOW(), d.*
FROM MyDB.data AS d WHERE d.primary_key_column = NEW.primary_key_column;
CREATE TRIGGER MyDB.data__au AFTER UPDATE ON MyDB.data FOR EACH ROW
INSERT INTO MyDB.data_history SELECT 'up...
What are the differences between poll and select?
I am referring to the POSIX standard select and poll system C API calls.
3 Answers
...
How to combine class and ID in CSS selector?
...is is super old and people keep finding it: don't use the tagNames in your selectors. #content.myClass is faster than div#content.myClass because the tagName adds a filtering step that you don't need. Use tagNames in selectors only where you must!
...
Fastest way to check if a string is JSON in PHP?
...
Checking first character of string for {, [ or first symbol of any other literal can potentially greatly speed this one up when many of incoming strings are expected to be non-JSON.
– Oleg V. Volkov
Se...
Adding additional data to select options using jQuery
...
HTML Markup
<select id="select">
<option value="1" data-foo="dogs">this</option>
<option value="2" data-foo="cats">that</option>
<option value="3" data-foo="gerbils">other</option>
</select&...
The object cannot be deleted because it was not found in the ObjectStateManager
... var project = context.Projects
.Include(p => p.Reports.Select(q => q.Issues.Select(r => r.Profession)))
.Include(p => p.Reports.Select(q => q.Issues.Select(r => r.Room)))
.SingleOrDefault(x => x.Id == id);
return proje...
SQL Query to concatenate column values from multiple rows in Oracle
...on on string aggregation techniques. A very common one is to use LISTAGG:
SELECT pid, LISTAGG(Desc, ' ') WITHIN GROUP (ORDER BY seq) AS description
FROM B GROUP BY pid;
Then join to A to pick out the pids you want.
Note: Out of the box, LISTAGG only works correctly with VARCHAR2 columns.
...