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Can table columns with a Foreign Key be NULL?

... a little bit to remember what needs to be done. If the data submitted is cast or interpreted as an empty string, it will fail. However, by explicitly setting the value to NULL when INSERTING or UPDATING, you're good to go. But this is the fun of programming, isn't it? Creating our own problems a...
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What is a wrapper class?

...ed to write a big code . However, the same can be achieved with the simple casting technique as code snippet can be achieved as below double d = 135.0; int integerValue = (int) d ; Though double value is explicitly converted to integer value also called as downcasting. ...
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Combining two lists and removing duplicates, without removing duplicates in original list

... Finally an answer that doesn't involve casting into sets! Kudos. – SuperFamousGuy Mar 25 '13 at 18:33 4 ...
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Convert data.frame columns from factors to characters

...ata frame. One option is to use the above but then use type.convert after casting everything to character, then recast factors back to character again. – Shane May 17 '10 at 18:56 ...
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How can I force division to be floating point? Division keeps rounding down to 0?

... You can cast to float by doing c = a / float(b). If the numerator or denominator is a float, then the result will be also. A caveat: as commenters have pointed out, this won't work if b might be something other than an integer or ...
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Increment a value in Postgres

...aracter varying + integer LINE 2: SET total = total + 1 Solved by casting the value as integer like this SET total = total::int + 1 – Stew-au Oct 31 '12 at 3:05 ...
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Return rows in random order [duplicate]

... Here's an example (source): SET @randomId = Cast(((@maxValue + 1) - @minValue) * Rand() + @minValue AS tinyint); share | improve this answer | ...
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how to concatenate two dictionaries to create a new one in Python? [duplicate]

... It does work in Python 3, but you have to cast the dict_items objects to real list objects. This is another case where Python 3 prioritised minor performance optimisations over simplicity and ease of use. – Carl Smith Apr 12 '17...
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g++ undefined reference to typeinfo

...Such access can happen when you create an object of the class, use dynamic_cast etc. [source] share | improve this answer | follow | ...
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How to convert DateTime? to DateTime

... You can use a simple cast: DateTime dtValue = (DateTime) dtNullAbleSource; As Leandro Tupone said, you have to check if the var is null before share | ...