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Laravel migration: unique key is too long, even if specified
...e that VARCHAR may have 1, 2 or 4 bytes for each length unit. Example: utf8_mb4 (4 bytes) -> 767 / 4 = 191. Otherwise utf8_general_ci for VARCHAR(X) with X < 85 ( 1 byte ) = O(85) , or utf8_general_ci for VARCHAR(X) with X >= 86 ( 2 bytes ) -> 767 / 2 = 383. Consider also other columns l...
is_null($x) vs $x === null in PHP [duplicate]
... three if you count isset() ) methods to determine if a value is null: is_null() and === null . I have heard, but not confirmed, that === null is faster, but in a code review someone strongly suggested that I use is_null() instead as it is specifically designed for the null-evaluation purpo...
How do I get a file extension in PHP?
...t few people know it. Meet pathinfo():
$ext = pathinfo($filename, PATHINFO_EXTENSION);
This is fast and built-in. pathinfo() can give you other information, such as canonical path, depending on the constant you pass to it.
Remember that if you want to be able to deal with non ASCII characters, y...
Context switches much slower in new linux kernels
...erformance problem in recent kernels has to do with the switch to the intel_idle cpuidle driver from acpi_idle, the driver used in older kernels. Sadly, the intel_idle driver ignores the user's BIOS configuration for the C-states and dances to its own tune. In other words, even if you completely dis...
UnicodeDecodeError: 'ascii' codec can't decode byte 0xef in position 1
...your terminal not being set to UTF-8. Here is my terminal
$ echo $LANG
en_GB.UTF-8
$ python
Python 2.7.3 (default, Apr 20 2012, 22:39:59)
[GCC 4.6.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> s = '(\xef\xbd\xa1\xef\xbd\xa5\xcf\x89\xef\xbd\xa5\xe...
Avoid duplicates in INSERT INTO SELECT query in SQL Server
...
Using NOT EXISTS:
INSERT INTO TABLE_2
(id, name)
SELECT t1.id,
t1.name
FROM TABLE_1 t1
WHERE NOT EXISTS(SELECT id
FROM TABLE_2 t2
WHERE t2.id = t1.id)
Using NOT IN:
INSERT INTO TABLE_2
(id, name)
SELECT t...
node.js require all files in a folder?
....
Working example of a loader:
var normalizedPath = require("path").join(__dirname, "routes");
require("fs").readdirSync(normalizedPath).forEach(function(file) {
require("./routes/" + file);
});
// Continue application logic here
...
How to create fixed space and flexible space bar button items programmatically?
..."Today" style:UIBarButtonItemStylePlain target:self action:@selector(update_baritem:)];
todayItem.tag = 2;
UIBarButtonItem *cashItem = [[UIBarButtonItem alloc] initWithTitle:@"Cash" style:UIBarButtonItemStylePlain target:self action:@selector(update_baritem:)];
cashItem.tag = 3;
UIBarButtonItem *c...
Javascript heredoc
... answered Jan 19 '13 at 16:19
Zv_oDDZv_oDD
1,5331616 silver badges2525 bronze badges
...
What is the purpose of class methods?
...alling class methods of an object is "better", or "more idiomatic": obj.cls_mthd(...) or type(obj).cls_mthd(...)?
– Alexey
Feb 27 '18 at 12:43
...