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What is the difference between Non-Repeatable Read and Phantom Read?
...n using "read uncommitted", it is incomplete. Snapshot isolation level (in SQL Server) is a much better alternative to read uncommitted. A valid use case for read uncommitted isolation level in a production system is rare IMO.
– BateTech
Mar 3 '18 at 13:09
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Optimistic vs. Pessimistic locking
...hown changes - the extra locking overhead is worth it.
Oh, and Microsoft SQL server defaults to page locking - basically the row you're reading and a few either side. Row locking is more accurate but much slower. It's often worth setting your transactions to read-committed or no-lock to avoid dead...
Select multiple records based on list of Id's with linq
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I get Local sequence cannot be used in LINQ to SQL implementations of query operators except the Contains operator. error when using LINQ2SQL datacontext.
– Mayank Raichura
Jan 30 '16 at 0:20
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What is the main difference between PATCH and PUT request?
...pdate code remotely.
One other possible use case is somewhat related to NoSQL databases, it is possible to store documents. Let say we use a JSON structure to send back and forth data from the server to the client. If we wanted to delete a field, we could use a syntax similar to the one in mongodb ...
SQlite Getting nearest locations (with latitude and longitude)
I have data with latitude and longitude stored in my SQLite database, and I want to get the nearest locations to the parameters I put in (ex. My current location - lat/lng, etc.).
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Facebook database design?
...as 100 friends, that means the table would contain 100'000'000'000 rows. MySQL partitioning?
– veidelis
Jun 4 '14 at 7:30
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How do I free my port 80 on localhost Windows?
...t 80 in windows.
IIS
World Wide Web Publishing service
IIS Admin Service
SQL Server Reporting services
Web Deployment Agent Service
Stop above applications if running and check!!!
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Why is there a difference in checking null against a value in VB.NET and C#?
...ditional advantage of mirroring the behaviour of NULL in (most if not all) SQL databases. This is also a more standard (than C#'s) interpretation of three-valued logic, as explained here.
The C# team made different assumptions about what NULL means, resulting in the behaviour difference you show. E...
JOIN queries vs multiple queries
...ou are joining 3 or more tables on different keys, often databases (i.e. mysql) can only use one index per table, meaning maybe one of the joins will be fast (and use an index) whereas the others will be extremely slow. For multiple queries, you can optimize the indexes to use for each query.
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Saving timestamp in mysql table using php
I have a field in a MySQL table which has a timestamp data type. I am saving data into that table. But when I pass the timestamp ( 1299762201428 ) to the record, it automatically saves the value 0000-00-00 00:00:00 into that table.
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