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In Django, how do I check if a user is in a certain group?
... more than a small number of users, since it will load large subsets users table into memory each time it runs.
– bhuber
Oct 8 '13 at 16:17
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Can someone explain mappedBy in JPA and Hibernate?
...irline that it is responsible for maintaining the values over in the other table. It is possible to tell an Entity it "owns" a column in a different table and is responsible for updating it. It's not something you usually want to do and can cause problems with the order SQL statements are executed...
How can I find which tables reference a given table in Oracle SQL Developer?
In Oracle SQL Developer , if I'm viewing the information on a table, I can view the constraints, which let me see the foreign keys (and thus which tables are referenced by this table), and I can view the dependencies to see what packages and such reference the table. But I'm not sure how to find wh...
How to get all columns' names for all the tables in MySQL?
Is there a fast way of getting all column names from all tables in MySQL , without having to list all the tables?
10 Answe...
Best way to test for a variable's existence in PHP; isset() is clearly broken
...didate for a terminal value because some_function has an extremely unpredictable return type (which is probably a bad sign in itself), then an additional boolean value, e.g. $found, could be used instead.
Thought experiment one: the very_null constant
PHP could theoretically provide a special cons...
Is there any difference between GROUP BY and DISTINCT
...river :: GroupBy : Distinct and screw => get list of unique values in a table column)
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Run function from the command line
...the function's name) into locals, a dictionary with a current local symbol table. The parantheses at the end will make the function be called.
update: if you would like the function to accept a parameter from the command line, you can pass in sys.argv[2] like this:
def myfunction(mystring):
pr...
SQL left join vs multiple tables on FROM line?
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The old syntax, with just listing the tables, and using the WHERE clause to specify the join criteria, is being deprecated in most modern databases.
It's not just for show, the old syntax has the possibility of being ambiguous when you use both INNER and OUTER j...
Hidden features of C
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Function pointers. You can use a table of function pointers to implement, e.g., fast indirect-threaded code interpreters (FORTH) or byte-code dispatchers, or to simulate OO-like virtual methods.
Then there are hidden gems in the standard library, such as qs...
Setting the default value of a DateTime Property to DateTime.Now inside the System.ComponentModel De
...lue). The issue for me was when I wanted to add a record directly into the table(using SQL) I had to provide the date(or leave it NULL). This is a much better solution. Thanks.
– Storm Muller
Sep 12 '18 at 18:32
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