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How do I create a file and write to it in Java?
...te that each of the code samples below may throw IOException. Try/catch/finally blocks have been omitted for brevity. See this tutorial for information about exception handling.
Note that each of the code samples below will overwrite the file if it already exists
Creating a text file:
PrintWriter...
Python argparse: default value or specified value
...
import argparse
parser = argparse.ArgumentParser()
parser.add_argument('--example', nargs='?', const=1, type=int)
args = parser.parse_args()
print(args)
% test.py
Namespace(example=None)
% test.py --example
Namespace(example=1)
% test.py --example 2
Namespace(example=2)
nargs...
Can you use an alias in the WHERE clause in mysql?
....
WHERE (sum(reviews.rev_rating)/count(reviews.rev_id))>5
BUT! Not all expressions will be allowed - using an aggregating function like SUM will not work, in which case you'll need to use a HAVING clause.
From the MySQL Manual:
It is not allowable to refer to a
column alias in a WHERE...
Composer install error - requires ext_curl when it's actually enabled
I'm trying to install Facebook PHP SDK with Composer. This is what I get
15 Answers
15...
When to use a key/value store such as Redis instead/along side of a SQL database?
...hich contains also use cases. Since redis is rather memory oriented it's really good for frequently updated real-time data, such as session store, state database, statistics, caching and its advanced data structures offers versatility to many other scenarios.
Redis, however, isn't NoSQL replacement...
Heap vs Binary Search Tree (BST)
... 1
Create worst n log(n) n
Delete worst log(n) log(n)
All average times on this table are the same as their worst times except for Insert.
*: everywhere in this answer, BST == Balanced BST, since unbalanced sucks asymptotically
**: using a trivial modification explained in thi...
.NET JIT potential error?
...di
00000012 push esi
00000013 mov ecx,ebx
00000015 call dword ptr ds:[00170210h] ; first unrolled call
0000001b push edi ; WRONG! does not increment oVec.y
0000001c push esi
0000001d mov ecx,ebx
0000001f ca...
Completion handler for UINavigationController “pushViewController:animated”?
...rface UINavigationController (CompletionHandler)
- (void)completionhandler_pushViewController:(UIViewController *)viewController
animated:(BOOL)animated
completion:(void (^)(void))completion;
@end
Implementation:
#import "UIN...
Nested Git repositories?
...
You may be looking for the Git feature called submodules. This feature helps you manage dependent repositories that are nested inside your main repository.
share
...
Cannot overwrite model once compiled Mongoose
...y have a schema defined, and then you are defining the schema again. Generally what you should do is instantiate the schema once, and then have a global object call it when it needs it.
For example:
user_model.js
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var userSchema...