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1052: Column 'id' in field list is ambiguous
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Confusing! Because nothing is actually removed from the SQL language, SQL-89 is a proper subset of SQL-92. The OP's syntax is valid SQL-92 syntax (and. unless I'm missing something, yours is valid SQL-89 syntax). I consider INNER JOIN to be 'depreciated' sinc...
Fast way to discover the row count of a table in PostgreSQL
...of rows due to the nature of MVCC. There is a way to speed this up dramatically if the count does not have to be exact like it seems to be in your case.
Instead of getting the exact count (slow with big tables):
SELECT count(*) AS exact_count FROM myschema.mytable;
You get a close estimate like ...
SSH configuration: override the default username [closed]
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Create a file called config inside ~/.ssh. Inside the file you can add:
Host *
User buck
Or add
Host example
HostName example.net
User buck
The second example will set a username and is hostname specific, while the first e...
How do I preview emails in Rails?
...iables the template expects.
This could be done with fixtures, but I typically prefer to just grab some pseudo-random real data. Remember - this is NOT a unit test - this is purely a development aid. It doesn't need to produce the same result every single time - in fact - it's probably better if ...
What do the result codes in SVN mean?
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U: Working file was updated
G: Changes on the repo were automatically merged into the working copy
M: Working copy is modified
C: This file conflicts with the version in the repo
?: This file is not under version control
!: This file is under version control but is mis...
SSH to Elastic Beanstalk instance
...ty group to add a rule for SSH access. The below will lock it down to only allow ingress from a specific IP address.
SSH | tcp | 22 | 22 | 192.168.1.1/32
Configure the environment of your Elastic Beanstalk Application
If you haven't made a key pair yet, make one by clicking Key Pairs below Sec...
How can I install a local gem?
If I download a .gem file to a folder in my computer, can I install it later using gem install ?
9 Answers
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How to remove unused C/C++ symbols with GCC and ld?
...scard unreferenced sections):
-Wl,--gc-sections
So if you had one file called test.cpp that had two functions declared in it, but one of them was unused, you could omit the unused one with the following command to gcc(g++):
gcc -Os -fdata-sections -ffunction-sections test.cpp -o test -Wl,--gc-se...
How to draw circle in html page?
...have a higher chance of it looking the same on different systems since not all computers/browsers have the same fonts installed.
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Getting a File's MD5 Checksum in Java
I am looking to use Java to get the MD5 checksum of a file. I was really surprised but I haven't been able to find anything that shows how to get the MD5 checksum of a file.
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