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Join vs. sub-query
...y important the readability of the code, because it is of great importance for later management of it... Let's remember the famous statement of Donald Knuth: "Premature optimization is the root of all evil (or at least most of it) in programming". However, naturally there are programming areas where...
lexers vs parsers
...sarily have to be of letters. But it
has to be of symbols which are atomic for the language
understood by parser/lexer.
Symbols for the lexer: ASCII characters.
Symbols for the parser: the particular tokens, which are terminal symbols of their grammar.
They analyse these symbols and try to match th...
How do I set a column value to NULL in SQL Server Management Studio?
...atement where you could:
Update table set ColumnName = NULL where [Filter for record here]
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PDO Prepared Inserts multiple rows in single query
...=0, $separator=","){
$result = array();
if($count > 0){
for($x=0; $x<$count; $x++){
$result[] = $text;
}
}
return implode($separator, $result);
}
$pdo->beginTransaction(); // also helps speed up your inserts.
$insert_values = array();
foreach($d...
What's the difference between integer class and numeric class in R
...uped together as "numeric" classes, the 2 most common of which are double (for double precision floating point numbers) and integer. R will automatically convert between the numeric classes when needed, so for the most part it does not matter to the casual user whether the number 3 is currently sto...
Embedding SVG into ReactJS
...
Update 2016-05-27
As of React v15, support for SVG in React is (close to?) 100% parity with current browser support for SVG (source). You just need to apply some syntax transformations to make it JSX compatible, like you already have to do for HTML (class → classNam...
What issues should be considered when overriding equals and hashCode in Java?
...
The theory (for the language lawyers and the mathematically inclined):
equals() (javadoc) must define an equivalence relation (it must be reflexive, symmetric, and transitive). In addition, it must be consistent (if the objects are not ...
Polymorphism with gson
...eAdapter. And you certainly don't need to do instanceofs or write adapters for the derived classes: just one adapter for the base class or interface, provided of course that you are happy with the default serialization of the derived classes. Anyway, here's the code (package and imports removed) (al...
What is the equivalent of “android:fontFamily=”sans-serif-light" in Java code?
...cs:
Create a typeface object given a family name, and option style
information. If null is passed for the name, then the "default" font
will be chosen. The resulting typeface object can be queried
(getStyle()) to discover what its "real" style characteristics are.
Note that excessively u...
CSRF protection with CORS Origin header vs. CSRF token
This question is about protecting against Cross Site Request Forgery attacks only.
2 Answers
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