大约有 5,600 项符合查询结果（耗时：0.0200秒） [XML]
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...
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...
How does password salt help against a rainbow table attack?
...for the purpose: let's say the attacker wants to build a rainbow table for 100,000 commonly used english words and typical passwords (think "secret"). Without salt she would have to precompute 100,000 hashes. Even with the traditional UNIX salt of 2 characters (each is one of 64 choices: [a–zA–Z...
Why is setTimeout(fn, 0) sometimes useful?
... 1.9)
function long_running(status_div) {
var result = 0;
// Use 1000/700/300 limits in Chrome,
// 300/100/100 in IE8,
// 1000/500/200 in FireFox
// I have no idea why identical runtimes fail on diff browsers.
for (var i = 0; i < 1000; i++) {
for (var j =...
What is the fastest method for selecting descendant elements in jQuery?
...hin 20 ops/sec to each other on most runs. Compared to 1 and 2, 4 is about 100-200 ops slower, and 5 is about 400 ops slower which is understandable because it goes through all descendants and not just children. Chart - tinyurl.com/25p4dhq
– Anurag
Jul 5 '10 at...
Fast Linux File Count for a large number of files
... in a particular directory when there are a very large number of files ( > 100,000).
18 Answers
...