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Why use the INCLUDE clause when creating an index?
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If the column is not in the WHERE/JOIN/GROUP BY/ORDER BY, but only in the column list in the SELECT clause.
The INCLUDE clause adds the data at the lowest/leaf level, rather than in the index tree.
This makes the index smaller because it's not part of the tree
INCLUDE co...
Avoiding instanceof in Java
...the: At least you don't have to deal with a growing if then else chain in order to add, remove or modify handlers. The code is less fragile to changes. So I'd say that for this reason it's superior to the instanceof approach. Anyway, I just wanted to give a valid alternative.
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Location of my.cnf file on macOS
...ams read config/startup files in the following locations (in the specified order):
/etc/my.cnf - Global
/etc/mysql/my.cnf - Global
SYSCONFDIR/my.cnf - Global
SYSCONFDIR represents the directory specified with the SYSCONFDIR option to CMake when MySQL was built. By default, this is the etc di...
C Macro definition to determine big endian or little endian machine?
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Code supporting arbitrary byte orders, ready to be put into a file called order32.h:
#ifndef ORDER32_H
#define ORDER32_H
#include <limits.h>
#include <stdint.h>
#if CHAR_BIT != 8
#error "unsupported char size"
#endif
enum
{
O32_LITTLE_E...
How to reset sequence in postgres and fill id column with new data?
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If you don't want to retain the ordering of ids, then you can
ALTER SEQUENCE seq RESTART WITH 1;
UPDATE t SET idcolumn=nextval('seq');
I doubt there's an easy way to do that in the order of your choice without recreating the whole table.
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What is “overhead”?
...ating it consumes energy and is overhead!
Overhead is something wasted in order to accomplish a task. The goal is to make overhead very very small.
In computer science lets say you want to print a number, thats your task. But storing the number, the setting up the display to print it and calling ...
How to sort my paws?
...ally going to use both in different ways.
Use the (temporal and spatial) order of the paw impacts to determine which paw is which.
Try to identify the "pawprint" based purely on its shape.
Basically, the first method works with the dog's paws follow the trapezoidal-like pattern shown in Ivo's qu...
What is the best way to use a HashMap in C++?
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The standard library includes the ordered and the unordered map (std::map and std::unordered_map) containers. In an ordered map the elements are sorted by the key, insert and access is in O(log n). Usually the standard library internally uses red black trees ...
SQLiteDatabase.query method
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whereArgs
specify the content that fills each ? in whereClause in the order they appear
the others
just like whereClause the statement after the keyword or null if you don't use it.
Example
String[] tableColumns = new String[] {
"column1",
"(SELECT max(column1) FROM table2) AS ma...
What are the differences between WCF and ASMX web services?
...ly that WCF would need to add a streamlined K.I.S.S. configuration mode in order to completely replace ASMX.
Example web.config for an ASMX webservice:
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<appSettings />
<system.web>
<compilation targetFramewor...