….sock –oltp-point-selects=1 –oltp-simple-ranges=0 –oltp-sum-ranges=0 –oltp-order-ranges=0 –oltp-distinct-ranges=0….sock –oltp-point-selects=9 –oltp-simple-ranges=0 –oltp-sum-ranges=0 –oltp-order-ranges=0 –oltp-distinct-ranges=0…
Comment: Is Synchronous Replication right for your app?
May 14, 2013 By 18 Comments
… point lookup queries later have to be aggregates ie running SUM() or MAX() for examples you provided.
Post: Benchmarking Percona Server TokuDB vs InnoDB
May 7, 2013 By 32 Comments
…_r10, sbtest$I_r100, sbtest$I_r1000, with roll-up sum for 10, 100, 1000 records in the main table. and…
Post: Percona XtraDB Cluster 5.5.30-23.7.4 for MySQL now available
April 17, 2013 By 2 Comments
… the range [0, 255] (inclusive). Quorum is computed using weighted sum over group members. Percona XtraDB Cluster binary will now be…
Post: Checking the subset sum set problem with set processing
May 16, 2011 By Leave a Comment
Hi, Here is an easy way to run the subset sum check from SQL, which you can then distribute with Shard…
Post: Distributed Set Processing with Shard-Query
May 14, 2011 By 27 Comments
…`), `count(*)`=`count(*)` + VALUES(`count(*)`), `sum(AirTime)`=`sum(AirTime)` + VALUES(`sum(AirTime)`), `sum(DepDelay)`=`sum(DepDelay)` + VALUES(`sum(DepDelay)`), `sum(DepDelay >= 0) flight_delayed`=`sum(DepDelay >= 0) flight_delayed… `origin_airport_id`, SUM(`count(*)`) AS `count(*)`, SUM(`sum(AirTime)`) AS `sum(AirTime)`, SUM(`sum(DepDelay)`) AS `sum(DepDelay)`, SUM(`sum(DepDelay >= 0) flight_delayed`) AS `sum(DepDelay >= 0) flight…
Post: Performance Schema tables stats
May 2, 2011 By 2 Comments
…_data_file COUNT_READ: 118218 COUNT_WRITE: 849692 SUM_NUMBER_OF_BYTES_READ: 1936883712 SUM_NUMBER_OF_BYTES_WRITE: 103557693440 *************************** 2. row…_data_file COUNT_READ: 22947 COUNT_WRITE: 20646 SUM_NUMBER_OF_BYTES_READ: 375963648 SUM_NUMBER_OF_BYTES_WRITE: 338264064 *************************** 3. row…
Post: Optimizing repeated subexpressions in MySQL
January 23, 2009 By 11 Comments
…(@sum, 6), pow(@sum, 7), pow(@sum, 8), pow(@sum, 10), pow(@sum, 11), pow(@sum, 12), pow(@sum, 13), pow(@sum, 14), pow(@sum, 15), pow(@sum, 16), pow(@sum, 17), pow(@sum…
Post: MySQL 5.6 vs MySQL 5.5 and the Star Schema Benchmark
March 11, 2013 By 7 Comments
…_name, index_name, count(*) pages, sum(is_old=’YES’) old, count(*) – sum(is_old=’YES’) hot, sum(number_records) records from information_schema…_name, index_name, count(*) pages, sum(is_old=’YES’) old, count(*) – sum(is_old=’YES’) hot, sum(number_records) records from information_schema…_name, index_name, count(*) pages, sum(is_old=’YES’) old, count(*) – sum(is_old=’YES’) hot, sum(number_records) records from information_schema…
Post: A rule of thumb for choosing column order in indexes
June 5, 2009 By 15 Comments
I wanted to share a little rule of thumb I sometimes use to decide which columns should come first in an index. This is not specific to MySQL, it’s generally applicable to any database server with b-tree indexes. And there are a bunch of subtleties, but I will also ignore those for the sake of …
