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Error: Tablespace for table xxx exists. Please DISCARD the tablespace before IMPORT
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A little late here but generally I've seen this problem occur when you get a 'tablespace full' error when running in a 'innodb_file_per_table' mode. Without going into too much detail (more here), the database server's tablespace is defined by the inno...
Why does Java's hashCode() in String use 31 as a multiplier?
... i == (i << 5) - i. Modern VMs do this sort of optimization automatically.
(from Chapter 3, Item 9: Always override hashcode when you override equals, page 48)
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Can attributes be added dynamically in C#?
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This really depends on what exactly you're trying to accomplish.
The System.ComponentModel.TypeDescriptor stuff can be used to add attributes to types, properties and object instances, and it has the limitation that you have to use...
PostgreSQL - max number of parameters in “IN” clause?
...ArrayOpExpr from IN/NOT IN, but this is only
* possible if the inputs are all scalars (no RowExprs) and there is a
* suitable array type available. If not, we fall back to a boolean
* condition tree with multiple copies of the lefthand expression.
* Also, any IN-list items that contain Vars are...
How do I remove the first characters of a specific column in a table?
...alue is ABCD123Stu1231 .
I want to remove first 4 chars from my table for all records
12 Answers
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Paused in debugger in chrome?
...nly takes a couple of hours (or less depending on your experience) to view all the options in the devTools UI and get comfortable with them. Please invest this time! It will help you immensely in your day-to-day debugging routine.
– CodeVortex
Aug 23 '16 at 8:3...
Function overloading by return type?
Why don't more mainstream statically typed languages support function/method overloading by return type? I can't think of any that do. It seems no less useful or reasonable than supporting overload by parameter type. How come it's so much less popular?
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How do I get bit-by-bit data from an integer value in C?
...ude <stdlib.h>
int *get_bits(int n, int bitswanted){
int *bits = malloc(sizeof(int) * bitswanted);
int k;
for(k=0; k<bitswanted; k++){
int mask = 1 << k;
int masked_n = n & mask;
int thebit = masked_n >> k;
bits[k] = thebit;
}
return bits;
}
in...
C++ performance vs. Java/C#
...p of a virtual machine which abstracts away the native architecture. Logically it would seem impossible for Java or C# to match the speed of C++ because of this intermediate step, however I've been told that the latest compilers ("hot spot") can attain this speed or even exceed it.
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Are “while(true)” loops so bad? [closed]
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I wouldn't say it's bad - but equally I would normally at least look for an alternative.
In situations where it's the first thing I write, I almost always at least try to refactor it into something clearer. Sometimes it can't be helped (or the alternative i...