473,322 Members | 1,431 Online
Bytes | Software Development & Data Engineering Community
Post Job

Home Posts Topics Members FAQ

Join Bytes to post your question to a community of 473,322 software developers and data experts.

How to update on a mysql myisam table becomes inconsistent with high concurrency?

Hi, I have a simple php script that queries a mysql database returns the content and updates a counter. This works fine until a concurrent limit of around 25 (simulated using ab) is reached at which point the update value becomes inconsistent e.g simulating 25 concurrent users hitting the script 500 times should set the counter to 500 but sometimes it is 498 or 499. I know the simulation isn't real life (thinking time etc) but 25 seems quite low. Would switching to innodb or using transactions solve the issue? My query is simply a select then an update. Thx
Nov 12 '10 #1
1 1673
omerbutt
638 512MB
yes it could be one of the possible options as ROW LEVEL AND TABLE LEVEL LOCKING DO MAKE A DIFF IN YOUR CASE NOT SURE BUT YOU MUST GO FOR IT
regards
Omer Aslam
Nov 12 '10 #2

Sign in to post your reply or Sign up for a free account.

Similar topics

4
by: Bruce A. Julseth | last post by:
My MySQL.user table (user, host, password) looks like the following: +---------+-----------+---------------------+ | user | host | password |...
0
by: David Bordas | last post by:
Hi list, I've got a little bug with MySQL. I can insert a row into my table but this row will not appear in the table :( Server is under linux redhat, MySQL is 3.23.56 installed from binary...
6
by: Matt Liverance | last post by:
I REALLY dont want to switch to oracle :( but I cant get these tables working any faster. I've got 2 dedicated servers, each with a slave, all run 32gig 15k rpm raid 5 on u320 perc raid...
6
by: Tom | last post by:
Hi Version of MySQL as yet undetermined but this will be running on White Box - Basically whats the maximum table size in GB that MySQL allows? We are developing an application that streams...
7
by: sime | last post by:
Hi, I have a blob field in a mysql database table. I want to copy a blob from one record to another. I am having trouble transferring the data via a php variable. Maybe I need to addslashes or...
9
by: expect | last post by:
Hello, Trying to get this MySql create table command to work, no luck. create sequence serial; CREATE TABLE outbound ( source char(100) default '', destination char(100) default '', sport...
5
by: PAUL | last post by:
Hello, I have 2 tables with a relationship set up in the dataset with vb ..net. I add a new record to the parent table then edit an existing child record to have the new parent ID. However when I...
4
by: whitemoss | last post by:
Hi, I've made some changes to my coding..but unfortunately, there were errors when compiling it..dunno how to solve it..hope anyone can help me...the errors: client.c: In function senddata:...
1
tolkienarda
by: tolkienarda | last post by:
i need to update a database table using variables in unusual places here are the update statements mysql_query("UPDATE 'grades' SET '$class' = '$grade' WHERE student='$student'");...
2
wadro21
by: wadro21 | last post by:
can someone tell me what is wrong with this? Error SQL query: CREATE TABLE uploads( upload_id int( 10 ) UNSIGNED NOT NULL AUTO_INCREMENT , file_name VARCHAR( 30 ) NOT NULL , file_size...
0
by: DolphinDB | last post by:
Tired of spending countless mintues downsampling your data? Look no further! In this article, you’ll learn how to efficiently downsample 6.48 billion high-frequency records to 61 million...
0
by: ryjfgjl | last post by:
ExcelToDatabase: batch import excel into database automatically...
0
isladogs
by: isladogs | last post by:
The next Access Europe meeting will be on Wednesday 6 Mar 2024 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM). In this month's session, we are pleased to welcome back...
1
isladogs
by: isladogs | last post by:
The next Access Europe meeting will be on Wednesday 6 Mar 2024 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM). In this month's session, we are pleased to welcome back...
0
by: Vimpel783 | last post by:
Hello! Guys, I found this code on the Internet, but I need to modify it a little. It works well, the problem is this: Data is sent from only one cell, in this case B5, but it is necessary that data...
0
by: jfyes | last post by:
As a hardware engineer, after seeing that CEIWEI recently released a new tool for Modbus RTU Over TCP/UDP filtering and monitoring, I actively went to its official website to take a look. It turned...
0
by: ArrayDB | last post by:
The error message I've encountered is; ERROR:root:Error generating model response: exception: access violation writing 0x0000000000005140, which seems to be indicative of an access violation...
1
by: Defcon1945 | last post by:
I'm trying to learn Python using Pycharm but import shutil doesn't work
0
by: Faith0G | last post by:
I am starting a new it consulting business and it's been a while since I setup a new website. Is wordpress still the best web based software for hosting a 5 page website? The webpages will be...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.