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How to remove first 10 characters from a string?
...
Substring has two Overloading methods:
public string Substring(int startIndex);//The substring starts at a specified character position and continues to the end of the string.
public string Substring(int startIndex, int length);//The substring starts at a specified character position and taking ...
What is the difference between varchar and nvarchar?
...
My two cents
Indexes can fail when not using the correct datatypes:
In SQL Server: When you have an index over a VARCHAR column and present it a Unicode String, SQL Server does not make use of the index. The same thing happens when you ...
What's the difference between '$(this)' and 'this'?
...e, in .each, the callback function commonly used allows for .each(function(index,element){/*scope*/}). In that scope, this == element is true.
jQuery callbacks use the apply function to bind the function being called with the current element. This element comes from the jQuery object's element arr...
Split Python Flask app into multiple files
...tes in the routes directory.
Structure
app.py
routes
__init__.py
index.py
users.py
__init__.py
from flask import Blueprint
routes = Blueprint('routes', __name__)
from .index import *
from .users import *
index.py
from flask import render_template
from . import routes
@routes.ro...
MySQL DISTINCT on a GROUP_CONCAT()
...5),(6),(7),(8),(9),(10);
then we can run this query:
SELECT
SUBSTRING_INDEX(
SUBSTRING_INDEX(tableName.categories, ' ', numbers.n),
' ',
-1) category
FROM
numbers INNER JOIN tableName
ON
LENGTH(tableName.categories)>=
LENGTH(REPLACE(tableName.categories, ' ', ''))+num...
How to make an array of arrays in Java
...lements and there are specialized Collections for different functionality (index-based lookup, sorting, uniqueness, FIFO-access, concurrency etc.).
While it's of course good and important to know about Arrays and their usage, in most cases using Collections makes APIs a lot more manageable (which i...
What exactly are iterator, iterable, and iteration?
...n iterator, or which defines a __getitem__ method that can take sequential indexes starting from zero (and raises an IndexError when the indexes are no longer valid). So an iterable is an object that you can get an iterator from.
An iterator is an object with a next (Python 2) or __next__ (Python 3...
MySQL Creating tables with Foreign Keys giving errno: 150
... of table test/t2:
FOREIGN KEY (t1_id) REFERENCES t1 (id)):
Cannot find an index in the referenced table where the
referenced columns appear as the first columns, or column types
in the table and the referenced table do not match for constraint.
It says that the problem is it can’t find an index...
How to get a string after a specific substring?
...
s1 = "hello python world , i'm a beginner "
s2 = "world"
print s1[s1.index(s2) + len(s2):]
If you want to deal with the case where s2 is not present in s1, then use s1.find(s2) as opposed to index. If the return value of that call is -1, then s2 is not in s1.
...
Getting the closest string match
...matches a substring of the query exactly. A simple approach is to begin by indexing the target: take all k-long substrings, put them in an array and sort them. Then take each k-long substring of the query and search the sorted index. Sort and search can be done in O(log n) time.
But storage can be ...