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“where 1=1” statement [duplicate]
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It's usually when folks build up SQL statements.
When you add and value = "Toyota" you don't have to worry about whether there is a condition before or just WHERE. The optimiser should ignore it
No magic, just practical
Example ...
“static const” vs “#define” vs “enum”
...sion for static arrays at function scope; both (2) and (3) can.
Under C99, all of these can be used for local arrays. Technically, using (1) would imply the use of a VLA (variable-length array), though the dimension referenced by 'var' would of course be fixed at size 5.
(1) cannot be used in place...
Insert into … values ( SELECT … FROM … )
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is it Necessary that we insert into all columns of the table
– maheshmnj
Feb 24 at 7:22
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Cast Int to enum in Java
... 0 or 1, i.e. a valid ordinal for that enum.
Note that in Java enums actually are classes (and enum values thus are objects) and thus you can't cast an int or even Integer to an enum.
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impr...
How to print to stderr in Python?
...to make your code Python3-ready. I guess this could be why many people actually like it!
– MarcH
Nov 18 '14 at 19:00
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How to identify server IP address in PHP
... This is NOT the server address! This is the address the remote browser calls the server, which is under control of the remote user. Use the answer by John K instead
– Ariel
Feb 12 '15 at 10:36
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Specify sudo password for Ansible
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For example, you might have a playbook something like this:
- hosts: all
vars_files:
- secret
tasks:
- name: Do something as sudo
service: name=nginx state=restarted
sudo: yes
Here we are including a file called secret which will contain our sudo password.
We will...
Error handling in C code
... your library as painless as possible think about these additions:
store all possible error-states in one typedef'ed enum and use it in your lib. Don't just return ints or even worse, mix ints or different enumerations with return-codes.
provide a function that converts errors into something huma...
Python Pandas: Get index of rows which column matches certain value
... frame (whose data may be gibabytes). What about dftest? Doesn't this also allocate a very large intermediate object where the returned index may be very small, or even empty. Are these magically optimized away using lazy views. If not then surely there must be an efficient way.
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How to determine if binary tree is balanced?
... some fraction of the minimum path length, like a half or a quarter.
It really doesn't matter usually. The point of any tree-balancing algorithm is to ensure that you do not wind up in the situation where you have a million nodes on one side and three on the other. Donal's definition is fine in the...