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How to add “on delete cascade” constraints?
...hy until you see "Constraints"), or you can query the information schema.
select *
from information_schema.key_column_usage
where position_in_unique_constraint is not null
share
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Does the order of LINQ functions matter?
... order by ((record.Score1 + record.Score2) / 2) descending
select new
{
Name = record.Name,
Average = ((record.Score1 + record.Score2) / 2)
};
If, for whatever reason, you decided to "optimize" the ...
How can I merge two hashes without overwritten duplicate keys in Ruby?
... and defaults without overwriting the destination hash, you may check with select if the key is already present in the destination hash. Here's the pure Ruby solution without Rails:
options = { "a" => 100, "b" => 200 }
defaults = { "b" => 254, "c" => 300 }
options.merge!(defaults.selec...
Storing time-series data, relational or non?
...evation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Index to support the columns identified in the WHERE clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a ...
C# switch statement limitations - why?
...values of switch labels are distinct (so that only one switch block can be selected for a given switch-expression)
Consider this code example in the hypothetical case that non-constant case values were allowed:
void DoIt()
{
String foo = "bar";
Switch(foo, foo);
}
void Switch(String val1...
How do you force Visual Studio to regenerate the .designer files for aspx/ascx files?
... Designer.cs file BY RIGHT CLICKING the aspx file in Solution Explorer and selecting delete. This worked for me in VS 2010.
– DeveloperDan
May 16 '12 at 21:02
...
One Activity and all other Fragments [closed]
...I used the single Activity approach and a Facebook style navigation. When selecting items from the navigation list I update a single Fragment container to display that section.
That said, having a single Activity also introduces a lot of complexities. Let's say you have an edit form, and for so...
Emacs bulk indent for Python
...
I use the following snippet. On tab when the selection is inactive, it indents the current line (as it normally does); when the selection is inactive, it indents the whole region to the right.
(defun my-python-tab-command (&optional _)
"If the region is active, s...
Maximum number of records in a MySQL database table
...g with multiple billions of entries? (which would probably just make your select statements melt down long before then)
– Kzqai
Apr 26 '10 at 19:35
2
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How can I escape square brackets in a LIKE clause?
...or the characters % and _.
Here's a good article with some more examples
SELECT columns FROM table WHERE
column LIKE '%[[]SQL Server Driver]%'
-- or
SELECT columns FROM table WHERE
column LIKE '%\[SQL Server Driver]%' ESCAPE '\'
...