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mysql :: insert into table, data from another table?
...ed by zerkms is the correct method. But, if someone looking to insert more extra column in the table then you can get it from the following:
INSERT INTO action_2_members (`campaign_id`, `mobile`, `email`, `vote`, `vote_date`, `current_time`)
SELECT `campaign_id`, `from_number`, 'example@domain.xyz'...
How do MySQL indexes work?
...lision number is high cause you'll only perform the second comparison (the string one) against the repeated hashes.
Unfortunately, using this technique, you still need to hit the table to compare the url field.
Wrap up
Some facts that you may consider every time you want to talk about optimizatio...
What is a Java ClassLoader?
...ollowing simple class:
public class HelloApp {
public static void main(String argv[]) {
System.out.println("Aloha! Hello and Bye");
}
}
If you run this class specifying the -verbose:class command-line option, so that it prints what classes are being loaded, you will get an output that...
Looking for a clear definition of what a “tokenizer”, “parser” and...
...hes extra context to the tokens -- this token is a number, that token is a string literal, this other token is an equality operator.
A parser takes the stream of tokens from the lexer and turns it into an abstract syntax tree representing the (usually) program represented by the original text.
Las...
Determine Whether Two Date Ranges Overlap
...a syntactical shortcut for what is a longer implementation, which includes extra checks to verify that the start dates are on or before the endDates. Deriving this from above:
If start and end dates can be out of order, i.e., if it is possible that startA > endA or startB > endB, then you a...
Word-wrap in an HTML table
...uld potentially preprocess the text and wrap only long words (say, > 40 chars) in the <span>.
– nornagon
Jun 2 '11 at 8:30
9
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Virtual functions and performance - C++
...an instruction cache miss like a non-virtual function.
In many cases, two extra cache misses are not a concern, but in a tight loop on performance critical code it can dramatically reduce performance.
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NodeJS - Error installing with NPM
...t least) 2 ways to resolve this.
Installing the Cygwin package cygutils-extra and use winln.
Use native Windows CMD in Admin mode.
For (1) you can create a proper symlink from within Cygwin shell by doing these steps:
# To make the Cygwin environment treat Windows links properly:
# Alternat...
How to check Oracle database for long running queries
...ions, nothing will show up.
COLUMN percent FORMAT 999.99
SELECT sid, to_char(start_time,'hh24:mi:ss') stime,
message,( sofar/totalwork)* 100 percent
FROM v$session_longops
WHERE sofar/totalwork < 1
/
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...
Passing Parameters JavaFX FXML
...age;
public class Main extends Application {
public static void main(String[] args) {
launch(args);
}
@Override
public void start(Stage primaryStage) {
// Create the first controller, which loads Layout1.fxml within its own constructor
Controller1 controll...