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PostgreSQL Autoincrement
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Yes, SERIAL is the equivalent function.
CREATE TABLE foo (
id SERIAL,
bar varchar);
INSERT INTO foo (bar) values ('blah');
INSERT INTO foo (bar) values ('blah');
SELECT * FROM foo;
1,blah
2,blah
SERIAL is just a create table time macro around sequences. You can not alter ...
Why is parenthesis in print voluntary in Python 2.7?
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In Python 2.x print is actually a special statement and not a function*.
This is also why it can't be used like: lambda x: print x
Note that (expr) does not create a Tuple (it results in expr), but , does. This likely results in the confusion between...
Removing colors from output
...cording to Wikipedia, the [m|K] in the sed command you're using is specifically designed to handle m (the color command) and K (the "erase part of line" command). Your script is trying to set absolute cursor position to 60 (^[[60G) to get all the OKs in a line, which your sed line doesn't cover.
(P...
Include constant in string without concatenating
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Yes it is (in some way ;) ):
define('FOO', 'bar');
$test_string = sprintf('This is a %s test string', FOO);
This is probably not what you were aiming for, but I think, technically this is not concatenation but a substitution and from this assumption, it inclu...
MySQL DROP all tables, ignoring foreign keys
Is there a nice easy way to drop all tables from a MySQL database, ignoring any foreign key constraints that may be in there?
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What's the difference between echo, print, and print_r in PHP?
...s, although such usage is rare; echo is slightly faster than print. (Personally, I always use echo, never print.)
var_dump prints out a detailed dump of a variable, including its type and the type of any sub-items (if it's an array or an object). print_r prints a variable in a more human-readable f...
Are PHP functions case sensitive?
I was digging through some code, and I found some calls to mySQL_fetch_array . Is PHP case sensitive about function names? I recall reading this somewhere but can't seem to find any reference to it.
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How to search file text for a pattern and replace it with a given value
...ull. This code is not fit for anything beyond a quick one-off script where all the data is backed up. For that reason, do NOT copy this code into your programs.
Here's a quick short way to do it.
file_names = ['foo.txt', 'bar.txt']
file_names.each do |file_name|
text = File.read(file_name)
ne...
What exactly does an #if 0 … #endif block do?
...h one important difference: Nesting is not a problem. Consider this code:
foo();
bar(x, y); /* x must not be NULL */
baz();
If I want to comment it out, I might try:
/*
foo();
bar(x, y); /* x must not be NULL */
baz();
*/
Bzzt. Syntax error! Why? Because block comments do not nest, and so (as ...
How do you access the matched groups in a JavaScript regular expression?
...not very intuitive. This lead to the proposal of the String.prototype.matchAll method. This new method is expected to ship in the ECMAScript 2020 specification. It gives us a clean API and solves multiple problems. It has been started to land on major browsers and JS engines as Chrome 73+ / Node 12+...