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How do I create delegates in Objective-C?
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@end
Then, in the body, we can check that our delegate handles messages by accessing our delegateRespondsTo struct, rather than by sending -respondsToSelector: over and over again.
Informal Delegates
Before protocols existed, it was common to use a category on NSObject to declare the methods a ...
How to change max_allowed_packet size
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Change in the my.ini or ~/.my.cnf file by including the single line under [mysqld] or [client] section in your file:
max_allowed_packet=500M
then restart the MySQL service and you are done.
See the documentation for further information.
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How do I use variables in Oracle SQL Developer?
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In SQL Developer, substitution variables defined by DEFINE seem to be persistent between query executions. If I change the variable value, but do not explicitly highlight the DEFINE line when executing, the previous value remains. (Is this because of the double && ...
Client-server synchronization pattern / algorithm?
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^^^^^^ this is by far the best answer, guys!
– hgoebl
Sep 18 '17 at 14:58
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Remove duplicates from an array of objects in JavaScript
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arr.filter((v,i,a)=>a.findIndex(t=>(t.id === v.id))===i)
Unique by multiple properties ( place and name )
arr.filter((v,i,a)=>a.findIndex(t=>(t.place === v.place && t.name===v.name))===i)
Unique by all properties (This will be slow for large arrays)
arr.filter((v,i,a)=&g...
Types in MySQL: BigInt(20) vs Int(20)
... http://dev.mysql.com/doc/refman/8.0/en/numeric-types.html
INT is a four-byte signed integer.
BIGINT is an eight-byte signed integer.
They each accept no more and no fewer values than can be stored in their respective number of bytes. That means 232 values in an INT and 264 values in a BIGINT...
How to set timer in android?
...;
setContentView(R.layout.main);
text = (TextView)findViewById(R.id.text);
text2 = (TextView)findViewById(R.id.text2);
text3 = (TextView)findViewById(R.id.text3);
Button b = (Button)findViewById(R.id.button);
b.setText("start");
b.setOnClickL...
INNER JOIN vs LEFT JOIN performance in SQL Server
...T JOIN is absolutely not faster than an INNER JOIN. In fact, it's slower; by definition, an outer join (LEFT JOIN or RIGHT JOIN) has to do all the work of an INNER JOIN plus the extra work of null-extending the results. It would also be expected to return more rows, further increasing the total e...
How to retrieve form values from HTTPPOST, dictionary or?
...g array of all keys in the form.
// NOTE: you specify the keys in form by the name attributes e.g:
// <input name="this is the key" value="some value" type="test" />
var keys = Request.Form.AllKeys;
// This will return the value for the keys.
var value1 = Request.Form.Get(...
Check whether an input string contains a number in javascript
...idate(){
var re = /^[A-Za-z]+$/;
if(re.test(document.getElementById("textboxID").value))
alert('Valid Name.');
else
alert('Invalid Name.');
}
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