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Good example of livelock?
...uld wait.
The proper fix is to always respect the lock heirarchy. Pick an order in which you acquire the locks and stick to that. For example if both threads always acquire lock1 before lock2, then there is no possibility of deadlock.
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mongodb/mongoose findMany - find all documents with IDs listed in array
... Kind of late to this discussion, but how would you ensure the order of the items returned matches the order of the array of items you provide in the array? Documents are not guaranteed to come out in any order unless you specify a sort. What if you want them sorted in the same order you...
What is an index in SQL?
...visited/scanned.
In SQL Server, a clustered index determines the physical order of data in a table. There can be only one clustered index per table (the clustered index IS the table). All other indexes on a table are termed non-clustered.
SQL Server Index Basics
SQL Server Indexes: The Basics
SQL...
How do I get a raw, compiled SQL query from a SQLAlchemy expression?
...q = DBSession.query(model.Name).distinct(model.Name.value) \
.order_by(model.Name.value)
Or just any kind of session.query().
Thanks to Nicolas Cadou for the answer! I hope it helps others who come searching here.
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How to check if a Constraint exists in Sql server?
... FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS where CONSTRAINT_NAME = 'UNIQUE_Order_ExternalReferenceId') BEGIN ALTER TABLE Order ADD CONSTRAINT UNIQUE_Order_ExternalReferenceId UNIQUE (ExternalReferenceId) END
– The Coder
Apr 15 '14 at 21:00
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Correct way to convert size in bytes to KB, MB, GB in JavaScript
...he size in bytes to be converted.
// pUnits: 'si'|'iec' si units means the order of magnitude is 10^3, iec uses 2^10
function prettyNumber(pBytes, pUnits) {
// Handle some special cases
if(pBytes == 0) return '0 Bytes';
if(pBytes == 1) return '1 Byte';
if(pBytes == -1) return '-1 By...
Hibernate throws MultipleBagFetchException - cannot simultaneously fetch multiple bags
... A List and a Set are not the same thing: a set does not preserve order
– Matteo
Mar 15 '12 at 15:36
17
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Is “else if” faster than “switch() case”? [duplicate]
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True, but with an if-else-if chain you can order the conditions based on how likely they are to be true.
– Dave Van den Eynde
Apr 20 '09 at 11:24
76...
What's the difference between Spring Data's MongoTemplate and MongoRepository?
.... You get very little implemented methods of any great practical value. In order to make it work you run into the Java configuration nonsense which you can spend days and weeks on without much help in the documentation.
Instead, go with the MongoTemplate route and create your own Data access layer...
Difference between Statement and PreparedStatement
...ons to the server is faster. As a rule of thumb network operations are an order of magnitude slower than disk operations which are an order of magnitude slower than in-memory CPU operations. Hence, any reduction in amount of data sent over the network will have a good effect on overall performance...