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How to add column if not exists on PostgreSQL?
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Here's a short-and-sweet version using the "DO" statement:
DO $$
BEGIN
BEGIN
ALTER TABLE <table_name> ADD COLUMN <column_name> <column_type>;
EXCEPTION
WHEN duplicate_column THE...
Is bool a native C type?
...kernel code uses bool, but I thought that bool was a C++ type. Is bool a standard C extension (e.g., ISO C90) or a GCC extension?
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Select count(*) from multiple tables
How can I select count(*) from two different tables (call them tab1 and tab2 ) having as result:
18 Answers
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How to set custom favicon in Express?
I recently started working in Node.js and in the app.js file there is this line:
13 Answers
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How can I save a screenshot directly to a file in Windows? [closed]
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You can code something pretty simple that will hook the PrintScreen and save the capture in a file.
Here is something to start to capture and save to a file. You will just need to hook the key "Print screen".
using System;
using System.Drawing;
using System.IO;
using System.Drawing.Imaging;...
Convert string to binary in python
...rent version 3.7.4): (1) bytearray expects an encoding (not just a string) and (2) map(bin, ...) will return the map object. For the first point, I use for instance bob.encoding('ascii')` as suggested by @Tao. For the second, point, using the join method, as in the other examples of @Kasramvd will ...
python: Change the scripts working directory to the script's own directory
... @EliCourtwright If __file__ is not already an absolute path, and the user has changed the working directory, then os.path.abspath will fail anyway.
– Arthur Tacca
Jan 17 '17 at 16:16
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How can a LEFT OUTER JOIN return more records than exist in the left table?
...ave a very basic LEFT OUTER JOIN to return all results from the left table and some additional information from a much bigger table. The left table contains 4935 records yet when I LEFT OUTER JOIN it to an additional table the record count is significantly larger.
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How to print a dictionary line by line in Python?
...came to the conclusion of my previous comment. You could send me your code and I can see if I'm any help.
– Darrel Holt
Dec 21 '16 at 20:54
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How to change the name of a Django app?
... have changed the name of an app in Django by renaming its folder, imports and all its references (templates/indexes). But now I get this error when I try to run python manage.py runserver
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