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Drop multiple tables in one shot in mysql
...e A has two children B and C. Then we can use the following syntax to drop all tables.
DROP TABLE IF EXISTS B,C,A;
This can be placed in the beginning of the script instead of individually dropping each table.
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Declaring variables inside loops, good practice or bad practice?
...their scope is restricted to inside the loop. It cannot be referenced nor called outside of the loop.
This way:
If the name of the variable is a bit "generic" (like "i"), there is no risk to mix it with another variable of same name somewhere later in your code (can also be mitigated using the -W...
Data Modeling with Kafka? Topics and Partitions
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When structuring your data for Kafka it really depends on how it´s meant to be consumed.
In my mind, a topic is a grouping of messages of a similar type that will be consumed by the same type of consumer so in the example above, I would just have a single topic and...
SQL SELECT speed int vs varchar
...ent date types:
int fields occupy between 2 and 8 bytes, with 4 being usually more than enough ( -2147483648 to +2147483647 )
character types occupy 4 bytes plus the actual strings.
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What's the difference between the atomic and nonatomic attributes?
...o are identical; "atomic" is the default behavior (note that it is not actually a keyword; it is specified only by the absence of nonatomic -- atomic was added as a keyword in recent versions of llvm/clang).
Assuming that you are @synthesizing the method implementations, atomic vs. non-atomic chang...
Traits in PHP – any real world examples/best practices? [closed]
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My personal opinion is that there is actually very little application for traits when writing clean code.
Instead of using traits to hack code into a class it is better to pass in the dependencies via the constructor or via setters:
class ClassName {
protected...
Is there a printf converter to print in binary format?
..._PATTERN"\n",
BYTE_TO_BINARY(m>>8), BYTE_TO_BINARY(m));
You need all the extra quotes unfortunately. This approach has the efficiency risks of macros (don't pass a function as the argument to BYTE_TO_BINARY) but avoids the memory issues and multiple invocations of strcat in some of the oth...
Is there a method to generate a UUID with go language
...ic range. rand.Read returns random bytes in the range 0-255, which are not all valid values for a UUID. As far as I can tell, this should be done for all the values in the slice though.
If you are on linux, you can alternatively call /usr/bin/uuidgen.
package main
import (
"fmt"
"log"
...
Swift Beta performance: sorting arrays
...t))
// [-1, 0, 2, 2, 5, 8, 1234]
// [-1, 0, 2, 2, 5, 8, 1234]
Both are called in the same program as written.
var x_swift = CInt[](count: n, repeatedValue: 0)
var x_c = CInt[](count: n, repeatedValue: 0)
for var i = 0; i < n; ++i {
x_swift[i] = CInt(random())
x_c[i] = CInt(random())
}...
How do lexical closures work?
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Python is actually behaving as defined. Three separate functions are created, but they each have the closure of the environment they're defined in - in this case, the global environment (or the outer function's environment if the loop is ...