keyspace name with the desired tablet type using the @ suffix. This can be specified as part of the connection as the database name, or can be changed on the fly through the USE command. For example, ks@master ~/my-vitess -example > mysql Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 1 Server version: 5.7.9-Vitess Percona Server (GPL), Release 29, Revision 11ad961 Copyright ~/my-vitess -example > mysql Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 2 Server version: 5.7.9-Vitess (Ubuntu) Copyright (c) 2000, 2019, Oracle and/or its affiliates

User Guide Query Rewriting Vitess works hard to create an illusion of the user having a single connection to a single database. In reality, a single query might interact with multiple databases and may level. Connection Pooling When a tablet talks with a MySQL to execute a query on behalf of a user, it does not use a dedicated connection per user, and instead will share the underlying connection between session as you can’t be sure it will continue executing queries on the same connection, and you can’t be sure if this connection will be used by other users later on. User-Defined Variables User defined

User Guide Query Rewriting Vitess works hard to create an illusion of the user having a single connection to a single database. In reality, a single query might interact with multiple databases and may level. Connection Pooling When a tablet talks with a MySQL to execute a query on behalf of a user, it does not use a dedicated connection per user, and instead will share the underlying connection between session as you can’t be sure it will continue executing queries on the same connection, and you can’t be sure if this connection will be used by other users later on. User-Defined Variables User defined

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 VTTablet Connection Pools and Sizing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . User Guide Query Rewriting Vitess works hard to create an illusion of the user having a single connection to a single database. In reality, a single query might interact with multiple databases and may level. Connection Pooling When a tablet talks with a MySQL to execute a query on behalf of a user, it does not use a dedicated connection per user, and instead will share the underlying connection between

User Guide Query Rewriting Vitess works hard to create an illusion of the user having a single connection to a single database. In reality, a single query might interact with multiple databases and may level. Connection Pooling When a tablet talks with a MySQL to execute a query on behalf of a user, it does not use a dedicated connection per user, and instead will share the underlying connection between session as you can’t be sure it will continue executing queries on the same connection, and you can’t be sure if this connection will be used by other users later on. User-Defined Variables User defined

~/my-vitess -example > mysql Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 2 Server version: 5.7.9-Vitess (Ubuntu) Copyright (c) 2000, 2019, Oracle and/or its affiliates Guide 20 Query Rewriting Vitess works hard to create an illusion of the user having a single connection to a single database. In reality, a single query might interact with multiple databases and may level. Connection Pooling When a tablet talks with a MySQL to execute a query on behalf of a user, it does not use a dedicated connection per user, and instead will share the underlying connection between

keyspace name with the desired tablet type using the @ suffix. This can be specified as part of the connection as the database name, or can be changed on the fly through the USE command. For example, ks@master following command: $ ./kmysql.sh Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 2 Server version: 5.7.9-Vitess Percona Server (GPL), Release 29, Revision 11ad961 Copyright performance is starting to tank - it’s okay, you’re prepared for this! Although the query guardrails and connection pooling are cool features that Vitess can offer to a single unsharded keyspace, the real value

keyspace name with the desired tablet type using the @ suffix. This can be specified as part of the connection as the database name, or can be changed on the fly through the USE command. For example, ks@master ~/my-vitess -example > mysql Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 1 Server version: 5.7.9-Vitess Percona Server (GPL), Release 29, Revision 11ad961 29 Copyright ~/my-vitess -example > mysql Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 2 Server version: 5.7.9-Vitess (Ubuntu) Copyright (c) 2000, 2019, Oracle and/or its affiliates

http://github.com/vitessio/vitess Growing with Vitess Vitess app server app server app server MainDB Connection pooling Deadlines Hot row protection Row count limit Blacklisting Growing with Vitess Vitess

Features • dynamic resharding • auto-failover • row-cache • limit inefficiency SQL • more client connection • replication lag optimization • multi data center Vitess Topo Vitess concepts • keyspace/keyspaceId