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How do I delete an exported environment variable?
...
Walkthrough of creating and deleting an environment variable in bash:
Test if the DUALCASE variable exists:
el@apollo:~$ env | grep DUALCASE
el@apollo:~$
It does not, so create the variable and export it:
el@apollo:~$ DUALCASE=1
el@apollo:~$ export DUALCASE
Check if it is there:
el@apol...
Split a string by a delimiter in python
How to split this string where __ is the delimiter
3 Answers
3
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How to copy a row and insert in same table with a autoincrement field in MySQL?
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Use INSERT ... SELECT:
insert into your_table (c1, c2, ...)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSERT column list and your SE...
How to avoid java.util.ConcurrentModificationException when iterating through and removing elements
...ther than the iterating one, the following code should work.
public class Test(){
private ArrayList<A> abc = new ArrayList<A>();
public void doStuff(){
for(int i = (abc.size() - 1); i >= 0; i--)
abc.get(i).doSomething();
}
public void removeA(A ...
Give all the permissions to a user on a DB
...son it doesn't seem to do anything. For exampe, I ran: grant ALL on schema test to userA; but after that userA still doesnt have access to read from the tables on schema test
– Diego
Mar 21 '14 at 9:32
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SQL select join: is it possible to prefix all columns as 'prefix.*'?
...}.{$field_name}`";
}
return implode(", ", $prefixed);
}
function test_prefixed_table_fields_wildcard()
{
global $wpdb;
$query = "
SELECT
" . prefixed_table_fields_wildcard($wpdb->posts, 'campaigns') . ",
" . prefixed_table_fields_wildcard($wpdb->posts, 'v...
Convert list to dictionary using linq and not worrying about duplicates
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LINQ solution:
// Use the first value in group
var _people = personList
.GroupBy(p => p.FirstandLastName, StringComparer.OrdinalIgnoreCase)
.ToDictionary(g => g.Key, g => g.First(), StringComparer.OrdinalIgnoreCase);
// Use the last value in group
var _peopl...
Find an item in List by LINQ?
...u don't need LINQ, just use:
int GetItemIndex(string search)
{
return _list == null ? -1 : _list.IndexOf(search);
}
If you are looking for the item itself, try:
string GetItem(string search)
{
return _list == null ? null : _list.FirstOrDefault(s => s.Equals(search));
}
...
Django set default form values
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@Phlip: Don't override View.get_form to set initial data. Any CBV with a FormMixin (basically all CBVs that create or edit data) can either use a class-level initial variable (for unchanging defaults) or you can override FormMixin.get_initial() to return ...
Equals(=) vs. LIKE
...the = comparison operator:
mysql> SELECT 'ä' LIKE 'ae' COLLATE latin1_german2_ci;
+-----------------------------------------+
| 'ä' LIKE 'ae' COLLATE latin1_german2_ci |
+-----------------------------------------+
| 0 |
+----------------------------------...