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Why is  appearing in my HTML? [duplicate]
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Try:
<?php
// Tell me the root folder path.
// You can also try this one
// $HOME = $_SERVER["DOCUMENT_ROOT"];
// Or this
// dirname(__FILE__)
$HOME = dirname(__FILE__);
// Is this a Windows host ? If it is, change this line to $WIN = 1;
$WIN = 0;
/...
Laravel Schema onDelete set null
...cument what options there are, but I think you can assume it's the default mysql values (see ../ vendor / laravel / framework / src / Illuminate / Database / Schema / Grammars / Grammar.php)
– Dirk Jan
Mar 23 at 14:47
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Cannot change column used in a foreign key constraint
... DELETE ) will wait till timeout or UNLOCK TABLES; is executed
http://dev.mysql.com/doc/refman/5.5/en/lock-tables.html
EDIT 2: OP asked for a more detailed explanation of the line "The type and definition of foreign key field and reference must be equal. This means your foreign key disallows chang...
B-Tree vs Hash Table
In MySQL, an index type is a b-tree, and access an element in a b-tree is in logarithmic amortized time O(log(n)) .
5 Answ...
在MongoDB中模拟Auto Increment - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
在MongoDB中模拟Auto IncrementMySQL用户多半都有Auto Increment情结，不过MongoDB缺省并没有实现，所以需要模拟一下，编程语言以PHP为例，代码大致如下所示：<?phpfunct...MySQL用户多半都有Auto Increment情结，不过MongoDB缺省并没有实现，所以...
NPM cannot install dependencies - Attempt to unlock something which hasn't been locked
...t the problem was. My ".npm" folder in my home directory was owned by the root user instead of myself. I'm not sure what happened to cause that. Maybe I installed node or npm as the root admin at one point. In any case I just ran sudo chown -R [username] .npm and I was finally able to run npm in...
John Carmack's Unusual Fast Inverse Square Root (Quake III)
... function in the Quake III source code which calculates the inverse square root of a float, 4x faster than regular (float)(1.0/sqrt(x)) , including a strange 0x5f3759df constant. See the code below. Can someone explain line by line what exactly is going on here and why this works so much faster t...
How to print SQL statement in codeigniter model
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Fatal error: Call to undefined method CI_DB_mysql_driver::get_compiled_select()
– itskawsar
Sep 25 '13 at 8:53
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In node.JS how can I get the path of a module I have loaded via require that is *not* mine (i.e. in
...in() calls), then resolve the package.json — which must always be in the root of the project — and pass to path.dirname():
let packagePath = path.dirname(require.resolve("moduleName/package.json"));
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How to define two fields “unique” as couple
... How would you handle this say if volume_number could be null? Mysql won't seem to enforce unique in that case.
– Greg
Jun 27 '11 at 17:28
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