Sponsored Content
Full Discussion: Multithreading program
Top Forums Shell Programming and Scripting Multithreading program Post 302358213 by adderek on Thursday 1st of October 2009 04:59:00 PM
Old 10-01-2009
1. Multithreading means "you must be stupid to do this in shell"
2. Loading 1 huge set of data at once is in general faster than loading dzylion of microsets in parallel
3. In Oracle you have SQLLoader and it has mode called "direct" - check if you cannot use similar thing in MySQL (I have no experience in MySQL)
4. If there is no option of direct loading of the data you might want to use bulk load methods
5. Loading in multiple threads means that you most probably are going to create dzylion of connections... if creation and closing of a single connection takes 1 second and inserting 1 row of data takes 0.0000000001 of a second... imagine how much slower would it work if you create multiple threads
6. Transaction is your friend - until you commit your application (executable compiled application) should be able to insert rows with only a minor performance decrease - if this is really really required by you then you might assume that there is a probable chance that you might need to create an application that loads row-by-row and commits the changes afterward.... really no bulk methods? I was thinking that MySQL is a developed database but it is not if there are no bulk operations.
 

9 More Discussions You Might Find Interesting

1. Programming

Multithreading in Pro*C

:confused: Hi! I have created a Multhreaded Application in Pro*C (using pthreads) with about 5 Threads running simultaneously. The Application is basically to Update a Centralized Table in Oracle, which updates different rows in the Table (Each Thread updates different rows!). The... (16 Replies)
Discussion started by: shaik786
16 Replies

2. Programming

multithreading on OSX

Hi all, I have a query about multithreading. What I would like to do is, at the start of my main update() function, start a couple of threads in parallel, once they are all complete carry on with my main update function. void update() { thread1->update(); // fluid solver ... (3 Replies)
Discussion started by: memoid
3 Replies

3. UNIX for Advanced & Expert Users

multithreading in UNIX

Hi, Can you please give me a suitable reference to learn multithreading programming in C in UNIX? Thanks (3 Replies)
Discussion started by: naan
3 Replies

4. Programming

MultiThreading using Pthreads

Situation: i have multiple pthread_create calls like this: pthread_create(...., ThreadFunc1,.....); pthread_create(...., ThreadFunc2,.....); . . which i am using to create multiple threads.All the "ThreadFunc<i>" functions are actually calling same function "Receive" of a class using same... (3 Replies)
Discussion started by: Sastra
3 Replies

5. IP Networking

how to do udp broadcast with multithreading

hello to all i want to use multithreading to my UDP broadcast server client program. will anyone help me by proving C code. i am working in fedora. also my requirement is POSIX compliance.please help me..... (0 Replies)
Discussion started by: moti12
0 Replies

6. Programming

how to do udp broadcast with multithreading

hello to all i want to use multithreading to my UDP broadcast server client program. will anyone help me by proving C code. i am working in fedora. also my requirement is POSIX compliance.please help me..... (6 Replies)
Discussion started by: moti12
6 Replies

7. Programming

Multithreading in reading file

Dear all, I am having a huge XML file, as below structure <EMPLOYEE> <RECORD id =aaa> <Salary>99999</Salary> <section>ssss</section> </RECORD> <RECORD id =bbb> <Salary>77777</Salary> <section>ssss</section> </RECORD> </EMPLOYEE> This is a 50 GB file I want to read this file in... (9 Replies)
Discussion started by: arunkumar_mca
9 Replies

8. What is on Your Mind?

Alarm interrupt and multithreading

Hi Friends any know how became a friend in this Android Programming Language (0 Replies)
Discussion started by: ljarun
0 Replies

9. Programming

Help with multithreading

I take this question of the The Linux Programming Interface: A Linux and Unix System Programming page 652 exercise 30.1 I want someone to explain the under line statement because it sounds complex to me couldn't understand anything 30-1 Modify the program (thread_incr.c) so that each loop in... (3 Replies)
Discussion started by: fwrlfo
3 Replies
MYSQL_UNBUFFERED_QUERY(3)						 1						 MYSQL_UNBUFFERED_QUERY(3)

mysql_unbuffered_query - Send an SQL query to MySQL without fetching and buffering the result rows.

SYNOPSIS
Warning This extension is deprecated as of PHP 5.5.0, and will be removed in the future. Instead, the MySQLi or PDO_MySQL extension should be used. See also MySQL: choosing an API guide and related FAQ for more information. Alternatives to this function include: oSee: Buffered and Unbuffered queries resource mysql_unbuffered_query (string $query, [resource $link_identifier = NULL]) DESCRIPTION
mysql_unbuffered_query(3) sends the SQL query $query to MySQL without automatically fetching and buffering the result rows as mysql_query(3) does. This saves a considerable amount of memory with SQL queries that produce large result sets, and you can start working on the result set immediately after the first row has been retrieved as you don't have to wait until the complete SQL query has been per- formed. To use mysql_unbuffered_query(3) while multiple database connections are open, you must specify the optional parameter $link_iden- tifier to identify which connection you want to use. o $query - The SQL query to execute. Data inside the query should be properly escaped. o $ link_identifier -The MySQL connection. If the link identifier is not specified, the last link opened by mysql_connect(3) is assumed. If no such link is found, it will try to create one as if mysql_connect(3) was called with no arguments. If no connection is found or established, an E_WARNING level error is generated. For SELECT, SHOW, DESCRIBE or EXPLAIN statements, mysql_unbuffered_query(3) returns a resource on success, or FALSE on error. For other type of SQL statements, UPDATE, DELETE, DROP, etc, mysql_unbuffered_query(3) returns TRUE on success or FALSE on error. Note The benefits of mysql_unbuffered_query(3) come at a cost: you cannot use mysql_num_rows(3) and mysql_data_seek(3) on a result set returned from mysql_unbuffered_query(3), until all rows are fetched. You also have to fetch all result rows from an unbuffered SQL query before you can send a new SQL query to MySQL, using the same $link_identifier. mysql_query(3). PHP Documentation Group MYSQL_UNBUFFERED_QUERY(3)
All times are GMT -4. The time now is 05:56 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy