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How to get the top 10 values in postgresql?
...dex on score.
Starting with version 8.4, you can also use the standard (SQL:2008) fetch first
select *
from scores
order by score desc
fetch first 10 rows only
As @Raphvanns pointed out, this will give you the first 10 rows literally. To remove duplicate values, you have to select distinct r...
Order by multiple columns with Doctrine
...or an example ->orderBy('a.fist_name ASC, a.last_name ASC') will output SQL something like this 'ORDER BY first_name ASC, last_name ASC ASC'. So this is SQL syntax error. Simply because default of the orderBy or addOrderBy is 'ASC'.
To add multiple order by's you need to use 'add' function. And...
Python glob multiple filetypes
...tern in patterns)
Then:
for filename in multiple_file_types("*.txt", "*.sql", "*.log"):
# do stuff
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PostgreSQL: Can you create an index in the CREATE TABLE definition?
...em to be any way of specifying an index in the CREATE TABLE syntax. PostgreSQL does however create an index for unique constraints and primary keys by default, as described in this note:
PostgreSQL automatically creates an index for each unique constraint and primary key constraint to enforce un...
How to completely uninstall Visual Studio 2010?
... "name like 'microsoft visual%'" call uninstall /nointeractive
Repeat for SQL etc by replacing visual% in above command with sql.
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Could not find an implementation of the query pattern
...ying to create a database connection using LINQ.
First I add a new LINQ to SQL class, and drag my table called "tblPersoon" into it.
...
Why are joins bad when considering scalability?
..., you mention "Materialized/indexed views". Are you talking about regular SQL views, or something else?
– slolife
Apr 30 '10 at 23:40
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How do I (or can I) SELECT DISTINCT on multiple columns?
... of the currently accepted answer by factor 10 - 15 (in my tests on PostgreSQL 8.4 and 9.1).
But this is still far from optimal. Use a NOT EXISTS (anti-)semi-join for even better performance. EXISTS is standard SQL, has been around forever (at least since PostgreSQL 7.2, long before this question w...
How do we count rows using older versions of Hibernate (~2009)?
...
What's the point of using an ORM if we end up coding SQL anyway?
– thermz
Apr 17 '12 at 15:35
Th...
nullable object must have a value
...on methods (e.g. Select, Where), the lambda function might be converted to SQL that might not behave identically to your C# code. For instance, C#'s short-circuit evaluated && and || are converted to SQL's eager AND and OR. This can cause problems when you're checking for null in your lambda...