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ERROR: Error 1005: Can't create table (errno: 121)
...ly for you, and it brought me here. I quote:
You will get this message if you're trying to add a constraint with a
name that's already used somewhere else
To check constraints use the following SQL query:
SELECT
constraint_name,
table_name
FROM
information_schema.table_constrain...
How can I check if my python object is a number? [duplicate]
...
Test if your variable is an instance of numbers.Number:
>>> import numbers
>>> import decimal
>>> [isinstance(x, numbers.Number) for x in (0, 0.0, 0j, decimal.Decimal(0))]
[True, True, True, True]
Thi...
What are the differences between type() and isinstance()?
...n versions do however offer extra goodies: isinstance (and issubclass) can now mean more than just "[an instance of] a derived class" (in particular, any class can be "registered" with an ABC so that it will show as a subclass, and its instances as instances of the ABC); and ABCs can also offer extr...
“No such file or directory” error when executing a binary
...
If anyone still got problems after installing the library mentioned above, try the following (it worked for me): sudo apt-get install libc6-i386 lib32stdc++6 lib32gcc1 lib32ncurses5 lib32z1
– ctitze
...
SQLAlchemy - Getting a list of tables
...les:
>>> metadata.tables.keys()
['posts', 'comments', 'users']
If you're using the declarative extension, then you probably aren't managing the metadata yourself. Fortunately, the metadata is still present on the baseclass,
>>> Base = sqlalchemy.ext.declarative.declarative_ba...
Getting the max value of an enum
... thinking this was really trival but an elegant solution was given. Also if you want to get the enum value use Convert.ToInt32() afterwards. This is for the google results.
– jdelator
Oct 15 '08 at 1:15
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How to query MongoDB with “like”?
...
Actually, it depends. If the query doesn't use an index, and must do a table scan, then it can certainly be expensive. If you're doing a 'starts with' regex query, then that can use an index. Best to run an explain() to see what's happening.
...
What is the difference between range and xrange functions in Python 2.X?
...f besides the anecdotal so far that it is faster) or what besides that is different about
28 Answers
...
What is lexical scope?
...t deduce the outer dynamic scope of a function, consider our last example. If we write something like this:
if(/* some condition */)
dummy1();
else
dummy2();
The call chain depends on a run time condition. If it is true, then the call chain looks like:
dummy1 --> fun()
If the condit...
Input text dialog Android
...rtDialog. You can customize the type of input allowed using setInputType, if you need.
If you're able to use a member variable, you can simply set the variable to the value of the EditText, and it will persist after the dialog has dismissed. If you can't use a member variable, you may need to use...