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PostgreSQL create table if not exists
...d to use the exact same spelling. If you don't, you need to use lower-case strings. See:
Are PostgreSQL column names case-sensitive?
pg_tables only contains actual tables. The identifier may still be occupied by related objects. See:
How to check if a table exists in a given schema
If the role e...
Limit a stream by a predicate
...suming the predicate doesn't throw or have a side-effect if executed a few extra times). The problem is doing it in the context of recursive decomposition (fork/join framework) that Streams use. Really, it's Streams that are horribly inefficient.
– Aleksandr Dubinsky
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Difference between and ?
...ludes a new ASP.NET pipeline and some configuration differences, hence the extra config sections.
However...
If you're running IIS 7.0 in integrated mode only, you shouldn't need to add the handlers to both sections. Adding it to system.web as well is a fallback for IIS 7.0 operating in classic ...
How can I dynamically create derived classes from a base class
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This bit of code allows you to create new classes with dynamic
names and parameter names.
The parameter verification in __init__ just does not allow
unknown parameters, if you need other verifications, like
type, or that they are mandatory...
Python Sets vs Lists
...move the object creation now. The setup phase of the timeit loops is only called once (docs.python.org/2/library/timeit.html#timeit.Timer.timeit).
– Ellis Percival
Sep 30 '14 at 10:09
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Django database query: How to get object by id?
Django automatically creates an id field as primary key.
6 Answers
6
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using lodash .groupBy. how to add your own keys for grouped output?
...t hard to wrap my head around. Can you explain the steps in between, especially the pairing and zipping (and the double zip, since _.object is an alias for _.zipObject).
– Benny Bottema
Jul 31 '15 at 9:17
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Stop an input field in a form from being submitted
...seems that the form fields are being submitted to the server with an empty string for the name. I inspected the post data using WebScarab and found that the data is being sent. For now I guess I will have to disable the fields to prevent them from being submitted.
– kldavis4
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How to add Google Analytics Tracking ID to GitHub Pages
... I have added them, however Google analytics say the Tracking is not installed. My page as specified in G-Analytics is http://avi-aryan.github.io
– Avi
Jul 15 '13 at 12:33
1
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mysql -> insert into tbl (select from another table) and some default values [duplicate]
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If you want to insert all the columns then
insert into def select * from abc;
here the number of columns in def should be equal to abc.
if you want to insert the subsets of columns then
insert into def (col1,col2, col3 ) select scol1,scol2,...