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Storing Data in MySQL as JSON
... who spends way too much time on stack exchange? When I have a record with 100 fields that I want to store and I only need to search on 3 or 4 of the fields, creating a table with 100 fields is nonsensical. You can store a customer record with his entire address book stored in 1 field in JSON, and j...
List comprehension rebinds names even after scope of comprehension. Is this right?
...expression. The less insane way found was single-value for clauses eg. sum100 = [s for s in [0] for i in range(1, 101) for s in [s + i]][-1], but just needs a comprehension-local var and works just as well in Python 3. I think "leaking" was the only way to set variable visible outside an expressio...
How to sort an array in Bash
... with. E.g., on my late-2012 iMac running OSX 10.11.1 with a Fusion Drive: 100-element array: ca. 0.03s secs. (qsort()) vs. ca. 0.005 secs. (sort + read -a); 1000-element array: ca. 0.375 secs. (qsort()) vs. ca. 0.014 secs (sort + read -a).
– mklement0
Oct 27 '...
How do you use the “WITH” clause in MySQL?
...les.
delimiter |
CREATE PROCEDURE WITH_EMULATOR(
recursive_table varchar(100), # name of recursive table
initial_SELECT varchar(65530), # seed a.k.a. anchor
recursive_SELECT varchar(65530), # recursive member
final_SELECT varchar(65530), # final SELECT on UNION result
max_recursion int unsigned, #...
Why do we use Base64?
... (or UTF-8) it will look like this:
72 101 108 108 111 10 119 111 114 108 100 33
The byte 10 is corrupted in some systems so we can base 64 encode these bytes as a Base64 string:
SGVsbG8sCndvcmxkIQ==
Which when encoded using ASCII looks like this:
83 71 86 115 98 71 56 115 67 110 100 118 99 10...
2015年硅谷最火的高科技创业公司都有哪些 - 资讯 - 清泛网 - 专注C/C++及内核技术
...发者， 介绍Spark性能超Hadoop百倍，算法实现仅有其1/10或1/100。在去年的Sort benchmark上，Spark用了23min跑完了100TB的排序，刷新了之前Hadoop保持的世界纪录。
Linkedin都采用了哪些大数据开源技术？
在 Linkedin，有很多数据产品，比如P...
Fastest Way to Serve a File Using PHP
...h nginx is, compared to reading and sending the file in php. Just think if 100 people are downloading a file: With php + apache, being generous, thats probably 100*15mb = 1.5GB (approx, shoot me), of ram right there. Nginx will just hand off sending the file to the kernel, and then it's loaded direc...
Find a value anywhere in a database
... drop it each time.
CREATE PROC SearchAllTables
(
@SearchStr nvarchar(100)
)
AS
BEGIN
-- Copyright © 2002 Narayana Vyas Kondreddi. All rights reserved.
-- Purpose: To search all columns of all tables for a given search string
-- Written by: Narayana Vyas Kondreddi
-- Site: http://vyaskn.tripo...
How to iterate through two lists in parallel?
...gated using the timeit() function where the number of repetitions used was 1000 times. One of the Python scripts that I had created to perform these investigations is given below. The sizes of the foo and bar lists had ranged from 10 to 1,000,000 elements.
Results:
For printing purposes: The perfor...
How to print color in console using System.out.println?
...ckgrounds
public static final String BLACK_BACKGROUND_BRIGHT = "\033[0;100m";// BLACK
public static final String RED_BACKGROUND_BRIGHT = "\033[0;101m";// RED
public static final String GREEN_BACKGROUND_BRIGHT = "\033[0;102m";// GREEN
public static final String YELLOW_BACKGROUND_BRIGH...