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How to fetch FetchType.LAZY associations with JPA and Hibernate in a Spring Controller
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You will have to make an explicit call on the lazy collection in order to initialize it (common practice is to call .size() for this purpose). In Hibernate there is a dedicated method for this (Hibernate.initialize()), but JPA has no equivalent of that. Of course you will have to make s...
MySQL, better to insert NULL or empty string?
...ifferent fields. Some of the fields are optional while some are mandatory. In my DB I have a table which holds all these values, is it better practice to insert a NULL value or an empty string into the DB columns where the user didn't put any data?
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How to delete a row by reference in data.table?
My question is related to assignment by reference versus copying in data.table . I want to know if one can delete rows by reference, similar to
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How to fix the Hibernate “object references an unsaved transient instance - save the transient insta
I receive following error when I save the object using Hibernate
30 Answers
30
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Why doesn't C++ have a garbage collector?
I'm not asking this question because of the merits of garbage collection first of all. My main reason for asking this is that I do know that Bjarne Stroustrup has said that C++ will have a garbage collector at some point in time.
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How to convert a column number (e.g. 127) into an Excel column (e.g. AA)
How do you convert a numerical number to an Excel column name in C# without using automation getting the value directly from Excel.
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Gradle: Execution failed for task ':processDebugManifest'
I'm getting a gradle error at building since yesterday - it just came randomly....
32 Answers
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What's the difference between [ and [[ in Bash? [duplicate]
...You no longer have to quote variables like mad because [[ handles empty strings and strings with whitespace more intuitively. For example, with [ you have to write
if [ -f "$file" ]
to correctly handle empty strings or file names with spaces in them. With [[ the quotes are unnecessary:
if [[ -f ...
Determine if Python is running inside virtualenv
Is it possible to determine if the current script is running inside a virtualenv environment?
16 Answers
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Do copyright dates need to be updated? [closed]
Every now and then I see a web site that has an old copyright date. In my mind, I always think "Look at the sucker who forgot to update his copyright year!" Then, while I was hard-coding a copyright year into the site I'm currently designing, it suddenly struck me:
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