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Class method decorator with self arguments?
...def countdown_decorator(func):
def func_wrapper():
for index in reversed(range(1, number+1)):
print("{}".format(index))
func()
return func_wrapper
return countdown_decorator
class MySuperClass():
def __init__(self, number):
sel...
Foreign key constraints: When to use ON UPDATE and ON DELETE
...
user_id INT,
user_name VARCHAR(50),
company_id INT,
INDEX company_id_idx (company_id),
FOREIGN KEY (company_id) REFERENCES COMPANY (company_id) ON...
) ENGINE=INNODB;
Let's look at the ON UPDATE clause:
ON UPDATE RESTRICT : the default : if you try to update a company...
Range references instead values
...
The short & direct answer: no, use the array index instead of the value
So the above code becomes:
package main
import "fmt"
type MyType struct {
field string
}
func main() {
var array [10]MyType
for idx, _ := range array {
array[idx].field = "...
PHP variables in anonymous functions
I was playing around with anonymous functions in PHP and realized that they don't seem to reach variables outside of them.
Is there any way to get around this problem?
...
How to change the foreign key referential action? (behavior)
...
Remember that MySQL keeps a simple index on a column after deleting foreign key. So, if you need to change 'references' column you should do it in 3 steps
drop original FK
drop an index (names as previous fk, using drop index clause)
create new FK
...
When are you supposed to use escape instead of encodeURI / encodeURIComponent?
... section B.2.1.2 escape and the introduction text of Annex B says:
... All of the language features and behaviours specified in this annex have one or more undesirable characteristics and in the absence of legacy usage would be removed from this specification. ...
... Programmers should not us...
Reference list item by index within Django template?
... thing is that I can't say {{ data.foo }}, where foo is a variable with an index value in it and not a property name.
– Mike DeSimone
Jan 10 '11 at 23:06
1
...
Javascript and regex: split string and keep the separator
...
var matches = [];
// Getting mached value and its index
var replaceName = splitter instanceof RegExp ? "replace" : "replaceAll";
var r = self[replaceName](splitter, function (m, i, e) {
matches.push({ value: m, index: i });
...
MongoDB: Combine data from multiple collections into one..how?
...h updates the merged data periodically. You'll probably want to run ensureIndex on the new collection to make sure queries you perform against it run quickly (keep in mind that your data is still inside a value key, so if you were to index comments_with_demographics on the comment created time, it ...
What is the most efficient/elegant way to parse a flat table into a tree?
...
Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentI...