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PostgreSQL - max number of parameters in “IN” clause?
...
explain select * from test where id in (values (1), (2));
QUERY PLAN
Seq Scan on test (cost=0.00..1.38 rows=2 width=208)
Filter: (id = ANY ('{1,2}'::bigint[]))
But if try 2nd query:
explain select * from test where id = an...
When should the volatile keyword be used in C#?
...t (40203Ch)]
00401045 call dword ptr [__imp_std::basic_ostream<char,std::char_traits<char> >::operator<< (402038h)]
}
0040104B xor eax,eax
0040104D pop ecx
0040104E ret
Looking at the output, the compiler has decided to use the ecx re...
Entity Framework DateTime and UTC
...ngth);
}
/// <inheritdoc />
public override char GetChar(int ordinal)
{
return source.GetChar(ordinal);
}
/// <inheritdoc />
public override long GetChars(int ordinal, long dataOffset, char[] buffer, int bufferOffset, ...
How and why does 'a'['toUpperCase']() in JavaScript work?
... same as anyObject.anyPropertyName when anyPropertyName hasn't problematic characters.
See Working with Objects, from the MDN.
The toUpperCase method is attached to the type String. When you call a function on a primitive value, here 'a', it is automatically promoted to an object, here a String :
...
Best way to create unique token in Rails?
...ittle bit of code in his Railscast on beta invitations. This produces a 40 character alphanumeric string.
Digest::SHA1.hexdigest([Time.now, rand].join)
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How do I perform an insert and return inserted identity with Dapper?
...uerySingle<int>( @"
INSERT INTO [MyTable] ([Stuff]) VALUES (@Stuff);
SELECT CAST(SCOPE_IDENTITY() as int)", new { Stuff = mystuff});
Note that on more recent versions of SQL Server you can use the OUTPUT clause:
var id = connection.QuerySingle<int>( @"
INSERT INTO [MyTable] ([Stuff])
...
How to select html nodes by ID with jquery when the id contains a dot?
...
@Tomalak in comments:
since ID selectors must be preceded by a hash #, there should be no ambiguity here
“#id.class” is a valid selector that requires both an id and a separate class to match; it's valid and not always totally redundant.
The correct...
Check if a string contains a string in C++
...lt;chrono>
std::string randomString( size_t len );
int main(int argc, char* argv[])
{
using namespace std::chrono;
const size_t haystacksCount = 200000;
std::string haystacks[haystacksCount];
std::string needle = "hello";
bool sink = true;
high...
Get selected value in dropdown list using JavaScript
How do I get the selected value from a dropdown list using JavaScript?
28 Answers
28
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How can prepared statements protect from SQL injection attacks?
...ample shows it (all examples in PHP/Mysql):
$expected_data = 1;
$query = "SELECT * FROM users where id=$expected_data";
will produce a regular query
SELECT * FROM users where id=1
while this code
$spoiled_data = "1; DROP TABLE users;"
$query = "SELECT * FROM users where id=$spoiled_da...