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Only parameterless constructors and initializers are supported in LINQ to Entities
...that Entity Framework attempts to pass the constructor call through to the SQL along with the rest of the LINQ query, and of course there is no way for SQL to go about constructing complex objects! By inserting the ToList() call you move the enumerable from a not-yet-executed SQL query to a concrete...
Is it possible to Pivot data using LINQ?
... 3).Sum(c => c.Qty)
});
GroupBy in Linq does not work the same as SQL. In SQL, you get the key and aggregates (row/column shape). In Linq, you get the key and any elements as children of the key (hierarchical shape). To pivot, you must project the hierarchy back into a row/column form of...
Do I need to create indexes on foreign keys on Oracle?
...t creates also an index... i.e. Jet Engine (MSAccess files, Firebird and MySQL)
– bubi
Apr 23 '15 at 15:19
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What scalability problems have you encountered using a NoSQL data store? [closed]
NoSQL refers to non-relational data stores that break with the history of relational databases and ACID guarantees. Popular open source NoSQL data stores include:
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Cause of a process being a deadlock victim
...5 to 10 minutes. I am currently not using NOLOCK as a hint to the MS SQL database engine. At the same time we have another process doing updates and inserts into the same database and same tables. The first process has started, recently to end prematurely with a message
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What are named pipes?
...ften, a commonly used standard default exists (much like port 80 for HTTP, SQL server uses port 1433 in TCP/IP; \\.\pipe\sql\query for a named pipe).
By setting up additional named pipes, you can have multiple DB servers running, each with its own request listeners.
The advantage of named pipes is...
How to thoroughly purge and reinstall postgresql on ubuntu? [closed]
Somehow I've managed to completely bugger the install of postgresql on Ubuntu karmic. I want to start over from scratch, but when I "purge" the package with apt-get it still leaves traces behind such that the reinstall configuration doesn't run properly.
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Copying data from one SQLite database to another
I have 2 SQLite databases with common data but with different purposes and I wanted to avoid reinserting data, so I was wondering if it was possible to copy a whole table from one database to another?
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How to list only the file names that changed between two commits?
...ite/rex/RexSimplify.java | 50 +++++++++++++++++-----
.../apache/calcite/sql/fun/SqlTrimFunction.java | 2 +-
.../apache/calcite/sql2rel/SqlToRelConverter.java | 16 +++++++
.../org/apache/calcite/util/SaffronProperties.java | 19 ++++----
.../org/apache/calcite/test/RexProgramTest.java | ...
The transaction manager has disabled its support for remote/network transactions
I'm using SQL Server and ASP.NET. I have the following function:
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