… Percona Server 5.6.10 sandbox: description=MySQL driver=com.mysql.jdbc.Driver connectionSpec=jdbc:mysql://127.0.0.1:5610/schemaspy driverPath… -t mysql -u msandbox_ro -p msandbox -meta schemaspy.meta.xml -o /var/www/schemaspy/ The -o directive tells SchemaSpy where to… additional tabs: Tables – Names, number of children, parents, count of columns, row counts, and comments — a great way for a high level…
Post: Replication in MySQL 5.6: GTIDs benefits and limitations - Part 2
May 30, 2013 By 6 Comments
… show where GTIDs shine and where improvements are expected. This is the second post of a series of articles focused on MySQL 5…_port=10002; mysql> start slave; # And then check the number of records from the t table s1> select count(*) from t; +———-+ | count(*) | +———-+ | 2…
Post: MySQL Query Patterns, Optimized - Webinar questions followup
June 3, 2013 By 2 Comments
On Friday I gave a presentation on “MySQL Query Patterns, Optimized” for Percona MySQL Webinars. If you missed it, you can still…? The tuple comparison you’re referring to is this example: WHERE (k1.keyword, k2.keyword, k3.keyword) = (‘espionage’, ‘nuclear-bomb’, ‘ejector… to count the movies per production year for each kind_id. It was more efficient in this case to force MySQL to…
Comment: Derived Tables and Views Performance
May 21, 2013 By 16 Comments
… parent, COUNT(*) AS Count FROM `menu` GROUP BY parent) Deriv1 ON a.id = Deriv1.parent WHERE a.parent=” . $parent); echo “”; while ($row = mysql_fetch_assoc($result)) { if ($row['Count'] > 0) { echo “” . $row[‘label…
Comment: INSERT INTO ... SELECT Performance with Innodb tables.
May 22, 2013 By 22 Comments
…struct(s), heap size 440760, 799203 row lock(s) MySQL thread id 38, OS thread handle 0x2b3c1c776940, query …SELECT ld.label_id, cai.inventory_id, COUNT(1) as installed_count from client_app_inventory cai inner join …to_device ld on (ld.device_id = d.id) where ld.trash = ‘f’ and cai.trash = ‘f’ and (…
Comment: Percona XtraBackup 2.1.3 for MySQL available for download
May 30, 2013 By 3 Comments
…max_used_connections=13 max_threads=2002 thread_count=6 connection_count=6 It is possible that mysqld could … You can use the following information to find out where mysqld died. If you see no messages after this… mysqld_safe mysqld from pid file /var/lib/mysql/srv-d2-mysql02.pid ended in an another …
Post: Is Synchronous Replication right for your app?
May 14, 2013 By 18 Comments
…effect on standard MySQL replication from this instance, since MySQL replication is asynchronous. What about semi-sync MySQL replication? It’…the database periodically? if( $last_count % 100 == 0 ) { $db->do( “UPDATE achievements SET count = $last_count where achievement = ‘killed_troll’”; } change …
Post: More on MySQL transaction descriptors optimization
April 26, 2013 By Leave a Comment
… avg(id) from sbtest$i force key (primary) select count(*) from sbtest$i WHERE k like ‘%0%’ SysBench-0.5/lua: POINT… –max-requests=0 –percentile=99 –mysql-user=root –mysql-db=sbtest8t1M –mysql-table-engine=INNODB –mysql-socket=/tmp/mysql.sock –oltp-point-selects=1 –oltp… –max-requests=0 –percentile=99 –mysql-user=root –mysql-db=sbtest8t1M –mysql-table-engine=INNODB –mysql-socket=/tmp/mysql.sock –oltp-point-selects=9 –oltp…
Post: Understanding the maximum number of columns in a MySQL table
April 8, 2013 By 5 Comments
… a modular system where the storage engines themselves owned their own metadata. This was a radical departure from the MySQL philosophy, and… into the SQL based MySQL, with MySQL 1.0 being released in 1995. The FoRM file specified what fields where on what screen…*FCOMP+288+ n_length+int_length+com_length > 65535L || int_count > 255) { my_message(ER_TOO_MANY_FIELDS, ER(ER_TOO…
Post: Virident vCache vs. FlashCache: Part 2
May 17, 2013 By 3 Comments
… purposes, I also include the numbers from the vCache test where the time-based flushing is enabled. As we’d expect… MySQL & Benchmark Configuration All benchmarks were conducted with the following: sysbench –num-threads=32 –test=tests/db/oltp.lua –oltp_tables_count…-time=7200 –max-requests=0 –percentile=95 \ –mysql-user=root –mysql-socket=/tmp/mysql.sock –mysql-table-engine=innodb \ –oltp-read-only=off run…
