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How to convert comma-separated String to List?
... "[\\s,]+" will also split on internal space within a comma separated token, it will treat both whitespace as a delimiter even when a comma is not present, instead of a comma plus any number of surrounding whitespace. "\\s*(,\\s*)+" will trim whitespace only around comma separated tokens, and a...
PostgreSQL: How to pass parameters from command line?
...-e -v v1=%constraints% -f test.sql
Now in your SQL code file, add the v1 token within your WHERE clause, or anywhere else in the SQL. Note that the tokens can also be used in an open SQL statement, not just in a file. Save this as test.sql:
SELECT * FROM myTable
WHERE NOT someColumn IN (:v1);
...
What and When to use Tuple? [duplicate]
...know about the Tuple type. Tuple is a class, not a struct. It thus will be allocated upon the managed heap. Each class instance that is allocated adds to the burden of garbage collection.
Note:
The properties Item1, Item2, and further do not have setters. You cannot assign them. The Tuple is immuta...
Cross-Origin Request Headers(CORS) with PHP headers
...LETE, PUT, PATCH, OPTIONS');
header('Access-Control-Allow-Headers: token, Content-Type');
header('Access-Control-Max-Age: 1728000');
header('Content-Length: 0');
header('Content-Type: text/plain');
die();
}
header('Access-Control-Allow-Origin: *');
...
NSString property: copy or retain?
...Name = [NSMutableString stringWithString:@"Chris"];
Person *p = [[[Person alloc] init] autorelease];
p.name = someName;
[someName setString:@"Debajit"];
The current value of the Person.name property will be different depending on whether the property is declared retain or copy — it will be @"D...
How do you add an action to a button programmatically in xcode
...ame = CGRectMake( 10, 80, 100, 30 );
UIButton *button = [[UIButton alloc] initWithFrame: buttonFrame];
[button setTitle: @"My Button" forState: UIControlStateNormal];
[button addTarget:self action:@selector(btnSelected:) forControlEvents:UIControlEventTouchUpInside];
...
How much is the overhead of smart pointers compared to normal pointers in C++?
...
shared_ptr has a significant overhead for creation because of it's memory allocation for the control block (which keeps the ref counter and a pointer list to all weak references). It has also a huge memory overhead because of this and the fact that std::shared_ptr is always a 2 pointer tuple (one t...
How can I include raw JSON in an object using Jackson?
...
@Sid there is no way to do that AND tokenization both efficiently. To support pass-through of unprocessed tokens would require additional state-keeping, which makes "regular" parsing somewhat less efficient. It is sort of like optimization between regular code ...
How to replace part of string by position?
.... The StringBuilder approach avoid this extra cost by working within a pre-allocated section of memory and moving chars round within it.
– redcalx
Apr 17 '18 at 15:52
...
MySQL maximum memory usage
...5-8 so called important settings. First off, not all of them matter - e.g. allocating a lot of resources to InnoDB and not using InnoDB doesn't make a lot of sense because those resources are wasted.
Or - a lot of people suggest to up the max_connection variable -- well, little do they know it also...