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How to speed up insertion performance in PostgreSQL
...ack-on-errors to "Transaction" by specifying Protocol=-1 in the connection string. By default psqlodbc uses "Statement" level, which creates a SAVEPOINT for each statement rather than an entire transaction, making inserts slower.
Use server-side prepared statements by specifying UseServerSidePrepare...
Arrow operator (->) usage in C
...ore legible foo*.bar. The whole mess of typedef-ing functions with all the extra parentheses would have been avoided as well.
– Marquis of Lorne
Jan 26 '15 at 6:04
...
Get data from fs.readFile
...file named filename.
If encoding is specified then this function returns a string. Otherwise it returns a buffer.
var text = fs.readFileSync('test.md','utf8')
console.log (text)
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How to test multiple variables against a value?
...a function that will compare multiple variables to an integer and output a string of three letters. I was wondering if there was a way to translate this into Python. So say:
...
What represents a double in sql server?
... I'll be darn; you're right! I wonder what SQL does with the extra bit; it's not used for the exponent. If it did, the exponent would go up to +-616 instead of +-308. Maybe to track NULL?
– Euro Micelli
Jul 30 '09 at 21:42
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What does .SD stand for in data.table in R
...mples below, this is particularly helpful for chaining together "queries" (extractions/subsets/etc using [). In particular, this also means that .SD is itself a data.table (with the caveat that it does not allow assignment with :=).
The simpler usage of .SD is for column subsetting (i.e., when .SDc...
How to add an object to an array
... aData) {
alert(aData[i].fullname());
}
/* convert array of object into string json */
var jsonString = JSON.stringify(aData);
document.write(jsonString);
Push object into array
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RAII and smart pointers in C++
...ance (and stealing an example from another answer):
void foo() {
std::string str;
// Do cool things to or using str
}
This works fine - but what if we want to return str? We could write this:
std::string foo() {
std::string str;
// Do cool things to or using str
return str;
}...
What is a 'semantic predicate' in ANTLR?
...hing:
grammar Numbers;
// entry point of this parser: it parses an input string consisting of at least
// one number, optionally followed by zero or more comma's and numbers
parse
: number (',' number)* EOF
;
// matches a number that is between 1 and 3 digits long
number
: Digit Digit Di...
Are PDO prepared statements sufficient to prevent SQL injection?
...xbf27. In gbk, that's an invalid multibyte character; in latin1, it's the string ¿'. Note that in latin1 and gbk, 0x27 on its own is a literal ' character.
We have chosen this payload because, if we called addslashes() on it, we'd insert an ASCII \ i.e. 0x5c, before the ' character. So we'd win...