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Cocoa Core Data efficient way to count entities
...a.. but what is an efficient way to make a count over an Entity-Type (like SQL can do with SELECT count(1) ...). Now I just solved this task with selecting all with NSFetchedResultsController and getting the count of the NSArray ! I am sure this is not the best way...
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mysql Foreign key constraint is incorrectly formed error
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I ran into this same problem with HeidiSQL. The error you receive is very cryptic. My problem ended up being that the foreign key column and the referencing column were not of the same type or length.
The foreign key column was SMALLINT(5) UNSIGNED and the refere...
Google Authenticator available as a public service?
...he content was great, but anyone using the first link should implement the SQL injection prevention methods, as there's some potential flaws. Look at the issues raised for the first one. Second link is perfect.
– Septronic
Oct 24 '15 at 11:58
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Merging two arrays in .NET
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@Yogee, easy to remember as it is like in SQL and also the nomenclature is connected with sets theory.
– Chris W
Nov 25 '15 at 12:24
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How do I use ROW_NUMBER()?
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Also this is true only for Sql-Server, as other RDMBS have optimized the select count
– yoel halb
Jul 19 '12 at 15:01
add a com...
Cannot delete or update a parent row: a foreign key constraint fails
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In my case: I just ran a large SQL file and one of the final statements failed, so I just wanna delete all tables, fix the syntax error, and rerun, making this exactly what I was looking for.
– ekerner
Nov 5 '14 at 17...
Does Java have buffer overflows?
...ion to behave badly.
This latter form is less likely but a poorly written sql string cleansing function widely distributed that had a problem such as this would be an inviting target.
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impro...
How to check if mysql database exists
Is it possible to check if a (MySQL) database exists after having made a connection.
21 Answers
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Show a number to two decimal places
...ther reasons you may want this is you dont want rounding... or in my cause SQL floats returned are not treated the same as normal floats which is a PHP math bug
– Amb3rL4nn
Feb 22 '17 at 5:48
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PHP Constants Containing Arrays?
...e so sure they all have 5.6. Anyone on windows server just now got the 5.6 sql server drivers from microsoft about a month ago.
– M H
Jul 9 '15 at 5:28
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