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Can I have multiple primary keys in a single table?
...s auto-incremented. This will work only in MyISAM. InnoDB will generate an error "ERROR 1075 (42000): Incorrect table definition; there can be only one auto column and it must be defined as a key".
DROP TABLE IF EXISTS `test`.`animals`;
CREATE TABLE `test`.`animals` (
`grp` char(30) NOT NULL,
...
How to add to an existing hash in Ruby
...plement this with the following: x['key'] = "value" however I am receiving errors. I should mention I am working with strings.
– Tom
Jul 28 '11 at 18:49
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Entity Framework is Too Slow. What are my options? [closed]
...ved a LOT of time in other simpler cases, with less code and less room for error and the queries are compiler verified and match the database. Less code is easier maintenance and less room for errors.
– JulianR
Dec 29 '11 at 18:11
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What is the difference between required and ng-required?
... Its worth mentioning that ng-required displays a default tooltip style error message saying 'this field is required', which is not always desired. I'm looking for a way to turn it off
– Adam Spence
Mar 13 '14 at 12:12
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What are major differences between C# and Java?
...ard to see how being forced to write an explicit try/finally block is less error-prone than a using statement, IMO. Most of C#'s "extra" features compared with Java mean that you can get away with writing less code, and that that code can be more readable.
– Jon Skeet
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Add column with number of days between dates in DataFrame pandas
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Nde - how exactly did it not work? Error or wrong values? Did you convert both A and B columns to datetime successfully?
– Ricky McMaster
Sep 24 '18 at 6:56
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Correct idiom for managing multiple chained resources in try-with-resources block?
...sort of obscure knowledge.
Also there's the "destruction". If there is an error condition, then you probably don't want to be flushing rubbish to a file that needs deleting (code for that not shown). Although, of course, deleting the file is also another interesting operation to do as error handlin...
What is the difference between PS1 and PROMPT_COMMAND
...ue of the last executed program. This is convenient to see if there was an error and the error code of the last program I ran in the terminal. Note the outer ' surrounding the entire PROMPT_COMMAND expression. It includes PS1 so that this variable is re-evaluated each time the PROMPT_COMMAND variabl...
Update Git submodule to latest commit on origin
... commands using && - meaning previous command must execute without error.
After a possible successful pull (if new stuff was found on the remote), I do a push to ensure that a possible merge-commit is not left behind on the client. Again, it only happens if a pull actually brought in new st...
How to save a BufferedImage as a File
...try block because, as per the API, the method throws an IOException "if an error occurs during writing"
Also explained are the method's objective, parameters, returns, and throws, in more detail:
Writes an image using an arbitrary ImageWriter that supports the given format to a File. If there is al...