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How to speed up insertion performance in PostgreSQL
...u've batched your work into big transactions, though.
INSERT or COPY in parallel from several connections. How many depends on your hardware's disk subsystem; as a rule of thumb, you want one connection per physical hard drive if using direct attached storage.
Set a high checkpoint_segments value an...
Best practice for creating millions of small temporary objects
What are the "best practices" for creating (and releasing) millions of small objects?
13 Answers
...
grepping using the “|” alternative operator
...Still, I'd delete an answer that is identical to the upvoted answer. Especially if had were 40k reputation under my belt.
– Attila Csipak
Sep 4 at 13:29
add a comment
...
Checking for a null int value from a Java ResultSet
... declaration. In which case your test is completely redundant.
If you actually want to do something different if the field value is NULL, I suggest:
int iVal = 0;
ResultSet rs = magicallyAppearingStmt.executeQuery(query);
if (rs.next()) {
iVal = rs.getInt("ID_PARENT");
if (rs.wasNull()) {
...
Inheriting class methods from modules / mixins in Ruby
...ors of the class. You can look at the ancestors of any class or module by calling its ancestors method:
module M
def foo; "foo"; end
end
class C
include M
def bar; "bar"; end
end
C.ancestors
#=> [C, M, Object, Kernel, BasicObject]
# ^ look, it's right here!
When you call a metho...
Display lines number in Stack Trace for .NET assembly in Release mode
...bugging is somewhat limited (stackoverflow.com/questions/113866). However callstacks are quite reliable even in optimized code, with exception of inlined functions and ocasional situations where tail call can be missing because call xxx / ret sequence was replaced with jmp xxx.
...
What is a “Bitmap heap scan” in a query plan?
... stay in memory, but you get the point).
A bitmap index scan will sequentially open a short-list of disk pages, and grab every applicable row in each one (hence the so-called recheck cond you see in query plans).
Note, as an aside, how clustering/row order affects the associated costs with either ...
How to recognize USB devices in Virtualbox running on a Linux host? [closed]
...and log in again
Attach to your PC the USB devices you want to be automatically mounted in the VM (virtual machine).
Open Virtualbox
Select your VM and go to "Machine" -> "Settings" -> "USB".
Check "Enable USB Controller"; click on the icon with the USB plug and the plus, and
click on the devi...
Parsing CSV files in C#, with header
...
Let a library handle all the nitty-gritty details for you! :-)
Check out FileHelpers and stay DRY - Don't Repeat Yourself - no need to re-invent the wheel a gazillionth time....
You basically just need to define that shape of your data - the fi...
Is there a fixed sized queue which removes excessive elements?
...ixed size. When I add an element and the queue is full, it should automatically remove the oldest element.
16 Answers
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