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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...
In a storyboard, how do I make a custom cell for use with multiple controllers?
... don't care about why these other attempts didn't work, feel free to leave now. I've got no magical workarounds for you, other than suggesting that you file a bug.)
A storyboard is, in essence, not much more than a collection of .xib files. When you load up a table view controller that has some pro...
How to work around the lack of transactions in MongoDB?
I know there are similar questions here but they are either telling me to switch back to regular RDBMS systems if I need transactions or use atomic operations or two-phase commit . The second solution seems the best choice. The third I don't wish to follow because it seems that many things coul...
Java: Integer equals vs. ==
...s I'm going to encounter, the value would be under 127. Good to catch this now though for the 5% where it isn't.
– Jeremy Goodell
Sep 3 '10 at 17:36
1
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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...
How to write DataFrame to postgres table?
...s 0.14 (released end of May 2014), postgresql is supported. The sql module now uses sqlalchemy to support different database flavors. You can pass a sqlalchemy engine for a postgresql database (see docs). E.g.:
from sqlalchemy import create_engine
engine = create_engine('postgresql://scott:tiger@lo...
“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
...
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...
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...
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.
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