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In Java, how do I convert a byte array to a string of hex digits while keeping leading zeros? [dupli
...ffffff" because of sign extension. So one might need to take the last two characters of the returned string.
– Marvo
Jul 27 '12 at 20:55
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\d is less efficient than [0-9]
...id it was probably more efficient to use a range or digit specifier than a character set.
5 Answers
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Insert into … values ( SELECT … FROM … )
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Try:
INSERT INTO table1 ( column1 )
SELECT col1
FROM table2
This is standard ANSI SQL and should work on any DBMS
It definitely works for:
Oracle
MS SQL Server
MySQL
Postgres
SQLite v3
Teradata
DB2
Sybase
Vertica
HSQLDB
H2
AWS RedShift
SA...
Algorithm to return all combinations of k elements from n
... takes an array of letters as an argument and a number of those letters to select.
71 Answers
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String concatenation vs. string substitution in Python
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did you make tests with real large strings (like 100000 chars)?
– drnk
Apr 29 '09 at 7:16
add a comment
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How can we match a^n b^n with Java regex?
...finalized pattern, with additional test cases, including one that's 10,000 characters long:
$tests = array(
'aaa', 'aaab', 'aaaxb', 'xaaab', 'b', 'abbb', 'aabb', 'aaabbbbb', 'aaaaabbb',
'', 'ab', 'abb', 'aab', 'aaaabb', 'aaabbb', 'bbbaaa', 'ababab', 'abc',
str_repeat('a', 5000).str_repeat('b',...
application/x-www-form-urlencoded or multipart/form-data?
...will fail.
The key is to choose an encoding and a boundary such that your selected boundary characters cannot appear in the encoded output. One simple solution is to use base64 (do not use raw binary). In base64 3 arbitrary bytes are encoded into four 7-bit characters, where the output character se...
Should I impose a maximum length on passwords?
...elves), but my bank has a requirement that passwords are between 6 and 8 characters long, and I started wondering...
20 A...
How can I read and parse CSV files in C++?
...0E+09
The code is written as a finite-state machine and is consuming one character at a time. I think it's easier to reason about.
#include <istream>
#include <string>
#include <vector>
enum class CSVState {
UnquotedField,
QuotedField,
QuotedQuote
};
std::vector<...
Enumerable.Empty() equivalent for IQueryable
...that doesn't create an actual empty IQueryable, which means it causes e.g. Union queries to be broken up into multiple queries instead of one.
– NetMage
May 22 '17 at 23:11
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