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Returning IEnumerable vs. IQueryable
...ifference is that IQueryable<T> is the interface that allows LINQ-to-SQL (LINQ.-to-anything really) to work. So if you further refine your query on an IQueryable<T>, that query will be executed in the database, if possible.
For the IEnumerable<T> case, it will be LINQ-to-object, ...
SQL Server: Is it possible to insert into two tables at the same time?
...e atomic, and can be sent to the server from a client application with one sql string in a single function call as if it were one statement. You could also apply a trigger to one table to get the effect of a single insert. However, it's ultimately still two statements and you probably don't want to...
SQL: deleting tables with prefix
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You cannot do it with just a single MySQL command, however you can use MySQL to construct the statement for you:
In the MySQL shell or through PHPMyAdmin, use the following query
SELECT CONCAT( 'DROP TABLE ', GROUP_CONCAT(table_name) , ';' )
AS statement F...
SQL/mysql - Select distinct/UNIQUE but return all columns?
I am trying to accomplish the following sql statement but I want it to return all columns is this possible? Something like:
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LINQ to SQL: Multiple joins ON multiple Columns. Is this possible?
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Joining on multiple columns in Linq to SQL is a little different.
var query =
from t1 in myTABLE1List // List<TABLE_1>
join t2 in myTABLE1List
on new { t1.ColumnA, t1.ColumnB } equals new { t2.ColumnA, t2.ColumnB }
...
You have to take a...
What makes a SQL statement sargable?
...t on the subject matter. So the question is, what does or doesn't make an SQL query sargable? Any documentation would be greatly appreciated.
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SQL - find records from one table which don't exist in another
I've got the following two SQL tables (in MySQL):
8 Answers
8
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Display names of all constraints for a table in Oracle SQL
...ch of the constraint for the multiple tables that I have created in Oracle SQL.
6 Answers
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Is there a performance difference between CTE , Sub-Query, Temporary Table or Table Variable?
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SQL is a declarative language, not a procedural language. That is, you construct a SQL statement to describe the results that you want. You are not telling the SQL engine how to do the work.
As a general rule, it is a good...
EF5: Cannot attach the file ‘{0}' as database '{1}'
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If you delete the DB file, it still stays registered with SqlLocalDB. Sometimes it fixes it to delete the DB. You can do this from the command line.
Open the "Developer Command Propmpt for VisualStudio" under your start/programs menu.
Run the following commands:
sqllocaldb.exe st...