June 19, 2013

Comment: MySQL Partitioning - can save you or kill you

… one partition. In one instance, I take advantage of that — I have 10 years of data, but usually queries hit the last week or… MySQL. PARTITIONs are scanned one at a time. (Please provide specific references if you find otherwise.) I would argue that single-row queries… equivalent rows. This is, in my experience, the main use case for PARTITIONing. I go into more details (and code) here: http://mysql.rjweb…

Post: Flexviews - part 3 - improving query performance using materialized views

10 | 6019 | 718031 | 3475 | +——+————-+————-+————-+ 10 rows in set (0.00 sec) You can also use this MV to display the total sales amount for

Post: Identifying the load with the help of pt-query-digest and Percona Server

…, not just for new connections as in MySQL. This is very helpful for measurement as otherwise …last line in the output the # MISC part, it tells you how much of “load” is not covered by top queries, we have 10% inquery that is taking up the longest sum of run time, query ranked #1. The first row in

Post: InnoDB Full-text Search in MySQL 5.6 (part 1)

10 rows in set (0.00 sec) mysql> delete from dir_test_innodb LIMIT 200000; Query OK, 200000 rows affected (8.65 sec) mysql

Post: Shard-Query EC2 images available

mysql> show table status like ‘ontime_fact’G *************************** 1. row *************************** Name: ontime_fact Engine: InnoDB Version: 10 Row_format: Compact Rows: 6697533 Avg_row

Post: How to find MySQL queries worth optimizing ?

Last_errno: 0 Killed: 0 # Query_time: 9.031233 Lock_time: 0.000086 Rows_sent: 0 Rows_examined: 10000000 Rows_affected: 0 Rowsrows which are found and returned up to the top level MySQL part for processing are counted the Rowsrows in set (0.00 sec) In this case we have 2 rows analyzed for each row

Post: Percona XtraDB Cluster: Failure Scenarios with only 2 nodes

10 rows in set (0.00 sec) percona2 mysql> insert into percona values (0,’percona2′,’daniel’); Query OK, 1 row affected (0.02 sec) percona2 mysql…. Now if you have only storage for 2 nodes, using the galera arbitrator … members = 2/3 (joined/total), act_id = 19, last_appl. = -1, protocols = 0/4/2 (gcs…

Post: Modeling MySQL Capacity by Measuring Resource Consumptions

query which touches less than 1 row in average which makes it very IO bound. So what If I am planning for

Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact

I have been working with Peter in preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a look at and benchmarking optimizer enhancements one by one. So in… new optimizer enhancement Index Condition Pushdown (ICP). Its available in both MySQL 5.6 and MariaDB 5.5 Now let’s take…