2 PluginBootService . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238 7 Reference 240 7.1 Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pagination Revision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258 Batch Split . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259 Optimization Rewrite gSphere-Proxy ShardingS phere-Sidecar Database Any My SQL/PostgreSQL My SQL/PostgreSQL Connections Count Cost High Low High Supported Languages Java Only Any Any Performance Low loss Relatively High loss

215 To distinguish databases and users in the same log . . . . . . . . . . . . . . . . . 216 To split into different log files . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 5.2.5 Scaling 2 PluginBootService . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250 7 Reference 251 7.1 Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pagination Revision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269 Batch Split . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270 Optimization Rewrite

12.1 ShadowAlgorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232 7 Reference 233 7.1 Sharding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pagination Revision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248 Batch Split . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 Optimization Rewrite gSphere-Proxy ShardingS phere-Sidecar Database Any My SQL/PostgreSQL My SQL/PostgreSQL Connections Count Cost High Low High Supported Languages Java Only Any Any Performance Low loss Relatively High loss

Running the test case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 518 12 Reference 520 12.1 Database Compatibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pagination Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 541 x Batch Split . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 542 Rewriting for Optimization ShardingSphere document ShardingSphere-JDBC ShardingSphere-Proxy Database Any MySQL/PostgreSQL Connections Count Cost More Less Heterogeneous language Java Only Any Performance Low loss Relatively High loss Decentralization

gSphere-Proxy ShardingS phere-Sidecar Database Any My SQL/PostgreSQL My SQL/PostgreSQL Connections Count Cost High Low High Supported Languages Java Only Any Any Performance Low loss Relatively High loss 0-beta SQL Parsing It is divided into lexical parsing and syntactic parsing. The lexical parser will split SQL into inseparable words, and then the syntactic parser will analyze SQL and extract the parsing id = 1; select id, name, age, count(*) as n, (select id, name, age, sex from table2 where id=2) as sid, yyyy from table1 where id=1; SELECT id , name , age , COUNT(*) AS n, ( SELECT

Running the test case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 489 12 Reference 491 ix 12.1 Database Compatibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pagination Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 512 Batch Split . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 513 Rewriting for Optimization ShardingSphere document ShardingSphere-JDBC ShardingSphere-Proxy Database Any MySQL/PostgreSQL Connections Count Cost More Less Heterogeneous language Java Only Any Performance Low loss Relatively High loss Decentralization

Running the test case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 380 7 Reference 381 7.1 Database Compatibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pagination Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400 Batch Split . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 401 Rewriting for Optimization top of standalone databases, enabling data security across underlying data sources. Read/write Split‐ ting Read/write splitting can be used to cope with business access with high stress. Sharding‐

Running the test case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 353 7 Reference 354 7.1 Database Compatibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pagination Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373 Batch Split . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 374 Rewriting for Optimization a single database, which can achieve data security across underlying data sources. Read/write Split‐ ting Read/write splitting can be used to cope with business access with high stress. Based on

it’s also the origin of the project name“ElasticJob” . 5.2.1 Sharding A concept in ElasticJob to split the job, enabling the job to be executed in distributed environment, where every single server only converting the sharding items’numbers to more readable business codes. For example, to horizontally split the databases according to the regions, database A stores data from Beijing, database B stores data ScheduleJobBootstrap and register them into the Spring IoC container automatically. Configuration reference: elasticjob: regCenter: serverLists: localhost:6181 namespace: elasticjob-springboot jobs:

FROM table_reference [, table_reference ...] [WHERE predicates] [GROUP BY {col_name | position} [ASC | DESC], ...] [ORDER BY {col_name | position} [ASC | DESC], ...] [LIMIT {[offset,] row_count | row_count row_count OFFSET offset}] • select_expr * | [DISTINCT] COLUMN_NAME [AS] [alias] | (MAX | MIN | SUM | AVG)(COLUMN_NAME | alias) [AS] [alias] | COUNT(* | COLUMN_NAME | alias) [AS] [alias] • table_reference table_reference tbl_name [AS] alias] [index_hint_list] | table_reference ([INNER] | {LEFT|RIGHT} [OUTER]) JOIN table_factor [JOIN ON conditional_expr | USING (column_list)] 4.2. 数据分片 31 Apache ShardingSphere