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Why use String.Format? [duplicate]
...er is not faster than concatenation. The myth that it is is supported by "tests" that actually do concatenation on different lines (or in a loop). When all concatenation is done on a single line, the compiler translates it into a string.append(paramaarray) call, which is the most efficient out of ...
Fastest way to count exact number of rows in a very large table?
...T(*) FROM MyBigtable WITH (NOLOCK)
-- NOLOCK here is for me only to let me test for this answer: no more, no less
1 runs, 5:46 minutes, count = 1,401,659,700
--Note, sp_spaceused uses this DMV
SELECT
Total_Rows= SUM(st.row_count)
FROM
sys.dm_db_partition_stats st
WHERE
object_name(objec...
What are metaclasses in Python?
...
Lets define a metaclass that will demonstrate how 'class:' calls it.
def test_metaclass(name, bases, dict):
print 'The Class Name is', name
print 'The Class Bases are', bases
print 'The dict has', len(dict), 'elems, the keys are', dict.keys()
return "yellow"
class TestName(object...
Generating CSV file for Excel, how to have a newline inside a value
...ll be trashed.
Following comments apply to Excel 2003, 2007 and 2013; not tested on Excel 2000
If you open the file by double-clicking on its name in Windows Explorer, everything works OK.
If you open it from within Excel, the results vary:
You have only ASCII characters in the file (and no BOM...
JPQL IN clause: Java-Arrays (or Lists, Sets…)?
...getResultList();
assertNotNull(actual);
assertEquals(2, actual.size());
Tested with EclipseLInk. With Hibernate 3.5.1, you'll need to surround the parameter with parenthesis:
String qlString = "select item from Item item where item.name IN (:names)";
But this is a bug, the JPQL query in the pr...
Do you use source control for your database items? [closed]
...proach tends make it faster to create/replace/update a database with the latest migrations, whereas a state-based approach makes actually creating changes. Which approach is better depends partly on whether you prioritize frequent database changes (use state-based) or frequent deployments to produc...
moving committed (but not pushed) changes to a new branch after pull
...anch, perform these steps:
git log
git diff {previous to last commit} {latest commit} > your_changes.patch
git reset --hard origin/{your current branch}
git checkout -b {new branch}
git apply your_changes.patch
I can imagine that there is a simpler approach for steps one and two.
...
Replace one character with another in Bash
...acters. It seems like bash's time complexity is worse than linear. A small test: x="$(tr -dc 'a-z \n' </dev/urandom | head -c1M)"; time y="$(tr ' ' \\- <<< "$x")"; time z="${x// /-}". With a string length of 1M (=2^20) tr took 0.04s and bash 5.0.11 took 17s. With 2M tr took 0.07s (expec...
Force CloudFront distribution/file update
... Invalidation request there: docs.amazonwebservices.com/AmazonCloudFront/latest/…
– j0nes
Jul 26 '12 at 6:50
For tho...
What is the native keyword in Java for?
..._HOME}/include/linux Main.c
java -Djava.library.path=. Main
Output:
4
Tested on Ubuntu 14.04 AMD64. Also worked with Oracle JDK 1.8.0_45.
Example on GitHub for you to play with.
Underscores in Java package / file names must be escaped with _1 in the C function name as mentioned at: Invoking J...