…matching some value in the group: This is one illustration of group by limitations in SQL language which is not offset by any MySQL specific extensions…City, Population City FROM City GROUP BY Country GROUPORDER BY Population DESC would simply return city with highest population for each country. In …
Post: A case for MariaDB's Hash Joins
May 31, 2012 By Leave a Comment
…with its EXPLAIN output as returned by MySQL 5.5 is as follows: SELECT…> ’1996-05-01′ GROUP BY o_orderkey ORDER BY num_items DESC LIMIT 10; …highest numeric value is the best one. So we can force the join algorithm used by setting appropriate values…
Post: Percona XtraDB Cluster reference architecture with HaProxy
June 20, 2012 By 63 Comments
… is to give step by step instructions, so…000000000000) does not match group state UUID (77c9da88-b965-…13:21:18 InnoDB: highest supported file format is…mysql> show global status like ‘wsrep_cluster_size’; +——————–+——-+ | Variable_name | Value | +——————–+——-+ | wsrep_…
Post: Benchmarking single-row insert performance on Amazon EC2
May 16, 2012 By 17 Comments
…highest …_in_group = 4 …by query cache on write heavy workload. OK, so that was all about the configuration of the EC2 instance and MySQL…BY RANGE (transactionid) (PARTITION p0 VALUES LESS THAN (100000000) ENGINE = InnoDB, PARTITION p1 VALUES LESS THAN (200000000) ENGINE = InnoDB, PARTITION p2 VALUES…
