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What does inverse_of do? What SQL does it generate?
...cumentation, it seems like the :inverse_of option is a method for avoiding SQL queries, not generating them. It's a hint to ActiveRecord to use already loaded data instead of fetching it again through a relationship.
Their example:
class Dungeon < ActiveRecord::Base
has_many :traps, :inverse_...
How to query MongoDB with “like”?
I want to query something with SQL's like query:
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Which SQL query is faster? Filter on Join criteria or Where clause?
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For inner joins it doesn't matter where you put your criteria. The SQL compiler will transform both into an execution plan in which the filtering occurs below the join (ie. as if the filter expressions appears is in the join condition).
Outer joins are a different matter, since the place of...
SQL Server CTE and recursion example
...eading an article on it. This article shows employee info with the help of Sql server CTE and recursion. It is basically showing employees and their manager info. I am not able to understand how this query works. Here is the query:
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SELECT * FROM X WHERE id IN (…) with Dapper ORM
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Dapper supports this directly. For example...
string sql = "SELECT * FROM SomeTable WHERE id IN @ids"
var results = conn.Query(sql, new { ids = new[] { 1, 2, 3, 4, 5 }});
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SQL Server equivalent to MySQL enum data type?
Does SQL Server 2008 have a a data-type like MySQL's enum ?
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How to compare only Date without Time in DateTime types in Linq to SQL with Entity Framework?
Is there a way to compare two DateTime variables in Linq2Sql but to disregard the Time part.
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MySQL/Amazon RDS error: “you do not have SUPER privileges…”
I'm attempting to copy my mysql database from an Amazon EC2 to an RDS:
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Select n random rows from SQL Server table
I've got a SQL Server table with about 50,000 rows in it. I want to select about 5,000 of those rows at random. I've thought of a complicated way, creating a temp table with a "random number" column, copying my table into that, looping through the temp table and updating each row with RAND() , and ...
How to truncate string using SQL server
i have large string in SQL Server. I want to truncate that string to 10 or 15 character
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