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How to map and remove nil values in Ruby
...
Ruby 2.7+
There is now!
Ruby 2.7 is introducing filter_map for this exact purpose. It's idiomatic and performant, and I'd expect it to become the norm very soon.
For example:
numbers = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your ...
Can PHP PDO Statements accept the table or column name as parameter?
...DO.
In that case you will simply want to filter and sanitize the data manually. One way to do this is to pass in shorthand parameters to the function that will execute the query dynamically and then use a switch() statement to create a white list of valid values to be used for the table name or col...
There is no ViewData item of type 'IEnumerable' that has the key 'xxx'
...ntains a SelectList with the same name as your DropDownList i.e. "submarket_0", the Html helper will automatically populate your DropDownList with that data if you don't specify the 2nd parameter which in this case is the source SelectList.
What happened with my error was:
Because the table contai...
Build tree array from flat array in javascript
...ibrary. It's, as far as I can tell, the fastest solution.
function list_to_tree(list) {
var map = {}, node, roots = [], i;
for (i = 0; i < list.length; i += 1) {
map[list[i].id] = i; // initialize the map
list[i].children = []; // initialize the children
}
for (i = 0; i ...
Stateless and Stateful Enterprise Java Beans
...s. If stateless session beans do not retain their state in between method calls, why is my program acting the way it is?
7 ...
'python' is not recognized as an internal or external command [duplicate]
... variables are set correctly. Any reason why?
– alpha_989
Sep 30 '17 at 23:40
superb! But, I think in my organization ...
How to solve “Fatal error: Class 'MySQLi' not found”?
...amazon linux, it would be something like sudo yum install php56-mysqlnd.x86_64 (pick the one matching to which version of php you have installed)
– auspicious99
Dec 3 '18 at 10:46
...
App store link for “rate/review this app”
... Note - the "type=Purple+Software" has to be there and it has to be literally "Purple Software" - it's not the name of your company, it's a codename for iPhone applications :) I wasted an hour before I figured this out...
– Kuba Suder
Oct 24 '11 at 11:27
...
How to declare a variable in a PostgreSQL query
...WITH () query which can work as a variable, or even tuple of variables. It allows you to return a table of temporary values.
WITH master_user AS (
SELECT
login,
registration_date
FROM users
WHERE ...
)
SELECT *
FROM users
WHERE master_login = (SELECT login
...