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PHP: How to remove all non printable characters in a string?
...ace is 14.79% faster
2048 chars str_replace 94.7111ms preg_replace 123.3189ms str_replace is 23.20% faster
4096 chars str_replace 227.7029ms preg_replace 258.3771ms str_replace is 11.87% faster
8192 chars str_replace 506.3410ms preg_replace 555.6269ms str_replace is 8.87% fas...
How do I create a unique constraint that also allows nulls?
...et_AllowNull
UNIQUE (TicketID, TicketUnique);
If IssueID 1 has ticket 123, the UNIQUE constraint will be on values (123, NULL). If IssueID 2 has no ticket, it will be on (NULL, 2). Some thought will show that this constraint cannot be duplicated for any row in the table, and still allows multip...
Is JavaScript an untyped language?
...licit compiler interjection, the instruction will error during run-time.
"12345" * 1 === 12345 // string * number => number
Strongly typed means there is a compiler, and it wants you an explicit cast from string to integer.
(int) "12345" * 1 === 12345
In either case, some compiler's featur...
How Pony (ORM) does its tricks?
...
@randomsurfer_123 probably not, we just need some time to implement it (maybe a week), and there are other tasks that are more important to us.
– Alexander Kozlovsky
Mar 18 '16 at 10:43
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How should I use try-with-resources with JDBC?
... = new PreparedStatementWrapper(con, query,
new Object[] { 123L, "TEST" }) {
@Override
protected void prepareStatement(Object... params) throws SQLException {
stat.setLong(1, Long.class.cast(params[0]));
stat.setString(2, String...
Regex that accepts only numbers (0-9) and NO characters [duplicate]
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In Javascript this is allowing the value 123-456 (\d)*$
– theB3RV
Feb 20 '17 at 15:39
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What's the fastest way to merge/join data.frames in R?
...bases as well.
library(plyr)
library(data.table)
library(sqldf)
set.seed(123)
N <- 1e5
d1 <- data.frame(x=sample(N,N), y1=rnorm(N))
d2 <- data.frame(x=sample(N,N), y2=rnorm(N))
g1 <- sample(1:1000, N, replace = TRUE)
g2<- sample(1:1000, N, replace = TRUE)
d <- data.frame(d1, g1,...
C# convert int to string with padding zeros?
...
Simply
int i=123;
string paddedI = i.ToString("D4");
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Reference: Comparing PHP's print and echo
...
echo 125;
ECHO 125
multi-value echo compiles to multiple opcodes
echo 123, 456;
ECHO 123
ECHO 456
Note that multi-value echo doesn't concatenate its arguments, but outputs them one-by-one.
Reference: zend_do_print, zend_do_echo.
Runtime differences
ZEND_PRINT is implemented as follows (ps...
In Java, what is the best way to determine the size of an object?
...
123
You should use jol, a tool developed as part of the OpenJDK project.
JOL (Java Object Layo...