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How to create id with AUTO_INCREMENT on Oracle?
...NCREMENT by 1),
c2 VARCHAR2(10)
);
Alternatively, Oracle 12 also allows to use a sequence as a default value:
CREATE SEQUENCE dept_seq START WITH 1;
CREATE TABLE departments (
ID NUMBER(10) DEFAULT dept_seq.nextval NOT NULL,
DESCRIPTION VARCHAR2(50) NOT NULL);
ALTER T...
How to make a HTML Page in A4 paper size page(s)?
...e the margins as you want them to be. */
}
}
In case you think you really need pixels (you should actually avoid using pixels), you will have to take care of choosing the correct DPI for printing:
72 dpi (web) = 595 X 842 pixels
300 dpi (print) = 2480 X 3508 pixels
600 dpi (high quality prin...
Calling closure assigned to object property directly
...sn't work on a StdClass.
Before PHP7, you'd have to implement the magic __call method to intercept the call and invoke the callback (which is not possible for StdClass of course, because you cannot add the __call method)
class Foo
{
public function __call($method, $args)
{
if(is_...
Using Python's os.path, how do I go up one directory?
...
os.path.abspath(os.path.join(os.path.dirname( __file__ ), '..', 'templates'))
As far as where the templates folder should go, I don't know since Django 1.4 just came out and I haven't looked at it yet. You should probably ask another question on SE to solve that issue....
Why can't non-default arguments follow default arguments?
...
All required parameters must be placed before any default arguments. Simply because they are mandatory, whereas default arguments are not. Syntactically, it would be impossible for the interpreter to decide which values match...
How to find all tables that have foreign keys that reference particular table.column and have values
...
This solution will not only display all relations but also the constraint name, which is required in some cases (e.g. drop constraint):
SELECT
CONCAT(table_name, '.', column_name) AS 'foreign key',
CONCAT(referenced_table_name, '.', referenced_column_n...
How do I tidy up an HTML file's indentation in VI?
How do I fix the indentation of his huge html files which was all messed up?
11 Answers
...
How to convert Nonetype to int or string?
I've got an Nonetype value x , it's generally a number, but could be None . I want to divide it by a number, but Python raises:
...
C# elegant way to check if a property's property is null
... off of PropertyC in this example and ObjectA, PropertyA and PropertyB can all be null.
19 Answers
...
How do I use extern to share variables between source files?
...ler is informed that a
variable exists (and this is its type); it does not allocate the
storage for the variable at that point.
A variable is defined when the compiler allocates the storage for
the variable.
You may declare a variable multiple times (though once is sufficient);
you may only defin...