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Why would you use Expression rather than Func?
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@bertl Delegate is what CPU sees (executable code of one architecture), Expression is what compiler sees (merely another format of source code, but still source code).
– codewarrior
May 5 '17 at 9:22
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How do I find duplicate values in a table in Oracle?
...or a given column and the count of their occurrences in an Oracle database table?
13 Answers
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NHibernate vs LINQ to SQL
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LINQ to SQL forces you to use the table-per-class pattern. The benefits of using this pattern are that it's quick and easy to implement and it takes very little effort to get your domain running based on an existing database structure. For simple applicatio...
MySQL LIKE IN()?
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Over 1 million rows in my table. REGEX arround 0.0009 and LIKE arround 0.0005. If more then 5 REGEX, arround 0.0012...
– David Bélanger
Nov 26 '11 at 5:24
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SQLite Reset Primary Key Field
I have a few tables in SQLite and I am trying to figure out how to reset the auto-incremented database field.
4 Answers
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Stored procedure slow when called from web, fast from Management Studio
... change:
ALTER PROCEDURE [dbo].[sproc]
@param1 int,
AS
SELECT * FROM Table WHERE ID = @param1
to:
ALTER PROCEDURE [dbo].[sproc]
@param1 int,
AS
DECLARE @param1a int
SET @param1a = @param1
SELECT * FROM Table WHERE ID = @param1a
Seems strange, but it fixed my problem.
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What's the difference between django OneToOneField and ForeignKey?
....title
Run python manage.py syncdb to execute the sql code and build the tables for your app in your database. Then use python manage.py shell to open a python shell.
Create the Reporter object R1.
In [49]: from thepub.models import Reporter, Article
In [50]: R1 = Reporter(first_name='Rick')
I...
Why am I getting this error: No mapping specified for the following EntitySet/AssociationSet - Entit
...MX file, you will see that none of the entities have an associated storage table in the SSDL.
That changes when you click the Generate Database From Model context menu item. The confusing part is that this action does more than simply generating a DDL script. In fact, it changes the EDMX file to in...
How does a PreparedStatement avoid or prevent SQL injection?
...);
If "user" came from user input and the user input was
Robert'); DROP TABLE students; --
Then in the first instance, you'd be hosed. In the second, you'd be safe and Little Bobby Tables would be registered for your school.
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Rails 4: List of available datatypes
... is not set to use :sql, then your schema.rb file wont be able to dump the table that uses types like :json. The schema will still be dumped for the tables that use default types but you'll see a comment for the table with special types like, "could not dump table...". Look here to set the schema_fo...