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Regular expression for exact match of a string
...tch" button and you will see why it matches. BTW remember '.' is a special char and good to escape it. (and good to think twice before down voting :D ).
– prageeth
Sep 29 '13 at 3:16
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JPA eager fetch does not join
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JPA doesn't provide any specification on mapping annotations to select fetch strategy. In general, related entities can be fetched in any one of the ways given below
SELECT => one query for root entities + one query for related mapped entity/collection of each root entity = (n+1) que...
Fastest way to check if a string is JSON in PHP?
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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...
What are the Ruby Gotchas a newbie should be warned about? [closed]
...as constants, so local variables should begin with a lowercase letter.
The characters $ and @ do not indicate variable data type as in Perl, but rather function as scope resolution operators.
To denote floating point numbers, one must follow with a zero digit (99.0) or an explicit conversion (99.to_...
IntelliJ shortcut to show a popup of methods in a class that can be searched
... the list or highlight the desired element. Press Enter to navigate to the selected element.
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Why use the SQL Server 2008 geography data type?
...tance < 500 * 1609.344
orderby distance
select f;
return q1.FirstOrDefault();
}
Then there is a very good reason to use Geography.
Explanation of spatial within Entity Framework.
Updated with Creating High Performance Spatial Databases
As I noted on Noe...
Effect of a Bitwise Operator on a Boolean in Java
...variables and operate on them bit by bit. In the case of integers, longs, chars this makes sense. These variables can contain the full range of values enforced by their size.
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sqlalchemy IS NOT NULL select
How can I add the filter as in SQL to select values that are NOT NULL from a certain column ?
3 Answers
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How to find largest objects in a SQL Server database?
...quite a bit understanding and determining the size of indices and tables:
SELECT
t.name AS TableName,
i.name as indexName,
sum(p.rows) as RowCounts,
sum(a.total_pages) as TotalPages,
sum(a.used_pages) as UsedPages,
sum(a.data_pages) as DataPages,
(sum(a.total_pages) *...
Computed / calculated / virtual / derived columns in PostgreSQL
...y as column?
The expression (looking like a column) is not included in a SELECT * FROM tbl, though. You always have to list it explicitly.
Can also be supported with a matching expression index - provided the function is IMMUTABLE. Like:
CREATE FUNCTION col(tbl) ... AS ... -- your computed expr...