together, and share the same regional availability. A cell typically contains a set of tablets, a vtgate pool, and app servers that use the Vitess cluster. With Vitess, all components can be configured and brought 44 Features • Performance – Connection pooling - Multiplex front-end application queries onto a pool of MySQL connections to optimize perfor- mance. – Query de-duping – Reuse results of an in-flight connection pooling feature uses Go’s concurrency support to map these lightweight connections to a small pool of MySQL connections. As such, Vitess can easily handle thousands of connections. Poorly written

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 Other relevant pool-related variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . preload_buffer_size NotSupported rbr_exec_mode NotSupported sql_log_off NotSupported thread_pool_high_priority_connection NotSupported thread_pool_prio_kickup_timer NotSupported transaction_write_set_extraction NotSupported gets transformed into a reserved connection, a fresh, clean connections is returned to the connection pool to replace it. Once the vtgate session that initiated the reserved connections disconnects, all reserved

preload_buffer_size NotSupported rbr_exec_mode NotSupported sql_log_off NotSupported thread_pool_high_priority_connection NotSupported thread_pool_prio_kickup_timer NotSupported transaction_write_set_extraction NotSupported type of system variables. 45 Design VTTablet Reserve Pool VTTablet will have a new pool named reserved pool. Connections in the reserved pool are tied to a specific session and are closed when the session Reserve a connection, execute the set statements, move the reserve connection to active transaction pool and execute begin and the query. • ReserveRelease: This closes the reserved connection and also rollback

preload_buffer_size NotSupported rbr_exec_mode NotSupported sql_log_off NotSupported thread_pool_high_priority_connection NotSupported thread_pool_prio_kickup_timer NotSupported transaction_write_set_extraction NotSupported gets transformed into a reserved connection, a fresh, clean connections is returned to the connection pool to replace it. Once the vtgate session that initiated the reserved connections disconnects, all reserved this type of system variables. Design VTTablet Reserve Pool VTTablet will have a new pool named reserved pool. Connections in the reserved pool are tied to a specific session and are closed when the session

preload_buffer_size NotSupported rbr_exec_mode NotSupported sql_log_off NotSupported thread_pool_high_priority_connection NotSupported thread_pool_prio_kickup_timer NotSupported transaction_write_set_extraction NotSupported gets transformed into a reserved connection, a fresh, clean connections is returned to the connection pool to replace it. Once the vtgate session that initiated the reserved connections disconnects, all reserved this type of system variables. Design VTTablet Reserve Pool VTTablet will have a new pool named reserved pool. Connections in the reserved pool are tied to a specific session and are closed when the session

configure both shardingsphere‐jdbc‐ spring‐boot‐starter and a spring‐boot‐starter of certain datasource pool(such as druid)? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 357 work with JPA? . . . 362 7.8.18 [DistSQL] How to set custom JDBC connection properties or connection pool properties when adding a data source using DistSQL? . . . . . . . . . . . . . . . 362 7.8.19 [DistSQL] Mybatis, Spring JDBC Template or direct use of JDBC; • Supports any third‐party database connection pool, such as DBCP, C3P0, BoneCP, HikariCP; • Support any kind of JDBC standard database: MySQL, PostgreSQL

preload_buffer_size NotSupported rbr_exec_mode NotSupported sql_log_off NotSupported thread_pool_high_priority_connection NotSupported thread_pool_prio_kickup_timer NotSupported transaction_write_set_extraction NotSupported together, and share the same regional availability. A cell typically contains a set of tablets, a vtgate pool, and app servers that use the Vitess cluster. With Vitess, all components can be configured and brought 56 Features • Performance – Connection pooling - Multiplex front-end application queries onto a pool of MySQL connections to optimize perfor- mance. – Query de-duping – Reuse results of an in-flight

configure both shardingsphere‐jdbc‐ spring‐boot‐starter and a spring‐boot‐starter of certain datasource pool(such as druid)? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345 work with JPA? . . . 350 7.8.18 [DistSQL] How to set custom JDBC connection properties or connection pool properties when adding a data source using DistSQL? . . . . . . . . . . . . . . . 350 7.8.19 [DistSQL] Mybatis, Spring JDBC Template or direct use of JDBC; • Supports any third‐party database connection pool, such as DBCP, C3P0, BoneCP, HikariCP; • Support any kind of JDBC standard database: MySQL, PostgreSQL

configure both shardingsphere‐jdbc‐ spring‐boot‐starter and a spring‐boot‐starter of certain datasource pool (such as druid)? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 459 8.5.1 DistSQL How to set custom JDBC connection properties or connection pool prop‐ erties when adding a data source using DistSQL? . . . . . . . . . . . . . . . . . 459 8.5 Mybatis, Spring JDBC Template, or direct use of JDBC; • Support any third‐party database connection pool, such as DBCP, C3P0, BoneCP, HikariCP; • Support any kind of JDBC standard database: MySQL, PostgreSQL

configure both shardingsphere‐jdbc‐ spring‐boot‐starter and a spring‐boot‐starter of certain datasource pool (such as druid)? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498 8.5.1 DistSQL How to set custom JDBC connection properties or connection pool prop‐ erties when adding a data source using DistSQL? . . . . . . . . . . . . . . . . . 498 8.5 Mybatis, Spring JDBC Template, or direct use of JDBC; • Support any third‐party database connection pool, such as DBCP, C3P0, BoneCP, HikariCP; • Support any kind of JDBC standard database: MySQL, PostgreSQL