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How do I force Postgres to use a particular index?
...s when datatypes don't match properly, you may need to include appropriate casts.
Your planner settings might be causing problems.
See also this old newsgroup post.
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Storing money in a decimal column - what precision and scale?
...onverting a floating point number back to an integer in step 3, don't just cast it - use a math function to round it first. This will usually be round, though in special cases it could be floor or ceil. Know the difference and choose carefully.
Store the type of a number alongside the value
This m...
Is the pImpl idiom really used in practice?
...about the implementation or just break the encapsulation by using terrible casting tricks. PIMPL solves/mitigates that.
Compilation time
Compilation time is decreased, since only the source (implementation) file of X needs to be rebuilt when you add/remove fields and/or methods to the XImpl class...
Why exactly is eval evil?
...nic or other)
pointers
restartable exceptions
self-modifying code
...and a cast of thousands.
If you find yourself having to use any of these powerful, potentially dangerous tools ask yourself three times "why?" in a chain. For example:
"Why do I have to use eval?"
"Because of foo." "Why ...
What's the meaning of interface{}?
...mment by @NickCraig-Wood. interface{} can point to anything and you need a cast/type assertion to use it.
package main
import (
. "fmt"
"strconv"
)
var c = cat("Fish")
var d = dog("Bone")
func main() {
var i interface{} = c
switch i.(type) {
case cat:
c.Eat() // Fish...
How does a language expand itself? [closed]
I am learning C++ and I've just started learning about some of Qt 's capabilities to code GUI programs. I asked myself the following question:
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What is a method group in C#?
...
You can cast a method group into a delegate.
The delegate signature selects 1 method out of the group.
This example picks the ToString() overload which takes a string parameter:
Func<string,string> fn = 123.ToString;
Console...
When is it appropriate to use UDP instead of TCP? [closed]
Since TCP guarantees packet delivery and thus can be considered "reliable", whereas UDP doesn't guarantee anything and packets can be lost. What would be the advantage of transmitting data using UDP in an application rather than over a TCP stream? In what kind of situations would UDP be the better c...
Concatenate two string literals
...ncatenate a std::string object with a literal it will make the appropriate casting for the literal.
But if you try to concatenate two literals, the compiler won't be able to find an operator that takes two literals.
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What does 'const static' mean in C and C++?
...e you saying const declaration implies static there as well? As in, if you cast const away, and modify the value, all values will be modified?
– Cookie
Mar 26 '14 at 20:44
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