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How do I delete a fixed number of rows with sorting in PostgreSQL?
...erm row identifier.
There's also oid but that only exists if you specifically ask for it when you create the table.
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What is the effect of encoding an image in base64?
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Here's a really helpful overview of when to base64 encode and when not to by David Calhoun.
Basic answer = gzipped base64 encoded files will be roughly comparable in file size to standard binary (jpg/png). Gzip'd binary files will ha...
Database design for audit logging
...a of what the old record looked like.
So for example, if you had a table called Opportunities to track sales deals, you would actually create two separate tables:
Opportunities
Opportunities_Content (or something like that)
The Opportunities table would have information you'd use to uniquely iden...
DBMS_OUTPUT.PUT_LINE not printing
...green plus icon to enable DBMS Output for a particular session.
Additionally, assuming that you don't want to print the literal "a.firstNamea.lastName" for every row, you probably want
FOR row IN quote_recs
LOOP
DBMS_OUTPUT.PUT_LINE( row.firstName || ' ' || row.lastName );
END LOOP;
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“You are on a branch yet to be born” when adding git submodule
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I've verified all of these things. When I check out the desired repo to another directory, it has many files, and a master branch. The repo I am trying to add this one to as a submodule is on the master branch, has no obvious problems (sta...
Test for equality among all elements of a single vector
I'm trying to test whether all elements of a vector are equal to one another. The solutions I have come up with seem somewhat roundabout, both involving checking length() .
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Passing a function with parameters as a parameter?
...nction wrapper that knows about the parameter and passes it to the actual callback implementation.
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Take the content of a list and append it to another list
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Take a look at itertools.chain for a fast way to treat many small lists as a single big list (or at least as a single big iterable) without copying the smaller lists:
>>> import itertools
>>> p = ['a', 'b', 'c']
>>> q = ['d', 'e', 'f']
>>> r = ['g', ...
C++ auto keyword. Why is it magic?
From all the material I used to learn C++, auto has always been a weird storage duration specifier that didn't serve any purpose. But just recently, I encountered code that used it as a type name in and of itself. Out of curiosity I tried it, and it assumes the type of whatever I happen to assig...
How to change default timezone for Active Record in Rails?
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I have decided to compile this answer because all others seem to be incomplete.
config.active_record.default_timezone determines whether to use Time.local (if set to :local) or Time.utc (if set to :utc) when pulling dates and times from the database. The default is :...