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How to copy a row and insert in same table with a autoincrement field in MySQL?
...
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 INSER...
How do I truncate a .NET string?
...inqpad extension methods)
var val = string.Concat(Enumerable.Range(0, 50).Select(i => i % 10));
foreach(var limit in new[] { 10, 25, 44, 64 })
new Perf<string> {
{ "newstring" + limit, n => new string(val.Take(limit).ToArray()) },
{ "concat" + limit, n => string....
How can I use “sizeof” in a preprocessor macro?
...produces p__LINE__ as a variable. You would need a preproc macro and use __CONCAT from sys/cdefs.h .
– Coroos
Mar 2 at 11:37
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Remove the last three characters from a string
...to remove a certain number of characters from the end of a string:
string.Concat("hello".Reverse().Skip(3).Reverse());
output:
"he"
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Datatype for storing ip address in SQL Server
...VARCHAR(15)) RETURNS BINARY(4)
AS
BEGIN
DECLARE @bin AS BINARY(4)
SELECT @bin = CAST( CAST( PARSENAME( @ip, 4 ) AS INTEGER) AS BINARY(1))
+ CAST( CAST( PARSENAME( @ip, 3 ) AS INTEGER) AS BINARY(1))
+ CAST( CAST( PARSENAME( @ip, 2 ) AS INTEGER) AS BINARY(1))
...
JSON formatter in C#?
...merable.Repeat(INDENT_STRING, --indentation)) + ch : ch.ToString()
select lineBreak == null
? openChar.Length > 1
? openChar
: closeChar
: lineBreak;
return String.Concat(result);
}
Output...
How to flatten tree via LINQ?
...IEnumerable<MyNode> Flatten(IEnumerable<MyNode> e) =>
e.SelectMany(c => Flatten(c.Elements)).Concat(new[] { e });
You can then filter by group using Where(...).
To earn some "points for style", convert Flatten to an extension function in a static class.
public static IEnume...
How can I append a string to an existing field in MySQL?
... Alternatively you can use CONCAT_WS which skips NULL values. For example SELECT CONCAT_WS(', ','First name',NULL,'Last Name'); gives 'First name, Last Name'
– BarneySchmale
Aug 8 '16 at 11:00
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Force drop mysql bypassing foreign key constraint
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If you are using phpmyadmin then this feature is already there.
Select the tables you want to drop
From the dropdown at the bottom of tables list, select drop
A new page will be opened having checkbox at the bottom saying
"Foreign key check", uncheck it.
Confirm the deletion by accepting ...
.NET - How can you split a “caps” delimited string into an array?
...aceCamelCase(this String input)
{
return new string(Enumerable.Concat(
input.Take(1), // No space before initial cap
InsertSpacesBeforeCaps(input.Skip(1))
).ToArray());
}
private static IEnumerable<char> InsertSpacesBeforeCaps(IEnumerable<...