Sharding Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 Key Generate Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 Load Balance Algorithm avg_state, sfunc = avg_transfn, finalfunc = avg_finalfn) CREATE TABLE agg_data_2k AS SELECT g FROM generate_series(0, 1999) g; CREATE SCHEMA alt_nsp1; ALTER AGGREGATE alt_agg3(int) OWNER TO regress_alter_generic_user2; avg_state, sfunc = avg_transfn, finalfunc = avg_finalfn) CREATE TABLE agg_data_2k AS SELECT g FROM generate_series(0, 1999) g; CREATE SCHEMA alt_nsp1; ALTER AGGREGATE alt_agg3(int) OWNER TO regress_alter_generic_user2;

Sharding Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 Key Generate Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 Load Balance Algorithm avg_state, sfunc = avg_transfn, finalfunc = avg_finalfn) CREATE TABLE agg_data_2k AS SELECT g FROM generate_series(0, 1999) g; CREATE SCHEMA alt_nsp1; ALTER AGGREGATE alt_agg3(int) OWNER TO regress_alter_generic_user2; avg_state, sfunc = avg_transfn, finalfunc = avg_finalfn) CREATE TABLE agg_data_2k AS SELECT g FROM generate_series(0, 1999) g; CREATE SCHEMA alt_nsp1; ALTER AGGREGATE alt_agg3(int) OWNER TO regress_alter_generic_user2;

keys in different physical tables in the same logic table can not perceive each other and thereby generate repeated sequences. It is possible to avoid clashes by restricting the initiative value and increasing solve this problem perfectly, (such as UUID and others) relying on some particular algorithms to generate unrepeated keys or introducing sequence generation services. We have provided several built‐in users implement self‐defined key generator. Built-In Key Generator UUID Use UUID.randomUUID() to generate the distributed key. SNOWFLAKE Users can configure the strategy of each table in sharding rule

keys in different physical tables in the same logic table can not perceive each other and thereby generate repeated sequences. It is possible to avoid clashes by restricting the initiative value and increasing solve this problem perfectly, (such as UUID and others) relying on some particular algorithms to generate unrepeated keys or introducing sequence generation services. We have provided several built‐in Apache ShardingSphere document, v5.0.0-beta Built-In Key Generator UUID Use UUID.randomUUID() to generate the distributed key. SNOWFLAKE Users can configure the strategy of each table in sharding rule

Sharding Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271 Key Generate Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278 Load Balance Algorithm it is very tricky to generate global unique primary keys for different data nodes. Self‐incrementing keys between different ac‐ tual tables within the same logical table generate repetitive primary keys solutions can perfectly solve this problem, such as UUID, which relies on specific al‐ gorithms to self‐generate non‐repeating keys, or by introducing primary key generation services. To facilitate users and

Sharding Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287 Key Generate Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298 Load Balance Algorithm it is very tricky to generate global unique primary keys for different data nodes. Self‐incrementing keys between different ac‐ tual tables within the same logical table generate repetitive primary keys solutions can perfectly solve this problem, such as UUID, which relies on specific al‐ gorithms to self‐generate non‐repeating keys, or by introducing primary key generation services. To facilitate users and

Sharding Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403 Key Generate Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 410 Load Balance Algorithm it is very tricky to generate global unique primary keys for different data nodes. Self‐incrementing keys between different ac‐ tual tables within the same logical table generate repetitive primary keys solutions can perfectly solve this problem, such as UUID, which relies on specific al‐ gorithms to self‐generate non‐repeating keys, or by introducing primary key generation services. To facilitate users and

Sharding Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 434 Key Generate Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 441 Load Balance Algorithm it is very tricky to generate global unique primary keys for different data nodes. Self‐incrementing keys between different ac‐ tual tables within the same logical table generate repetitive primary keys solutions can perfectly solve this problem, such as UUID, which relies on specific al‐ gorithms to self‐generate non‐repeating keys, or by introducing primary key generation services. To facilitate users and

ame> (+): # 分片算法名称 type: # 分片算法类型 props: # 分片算法属性配置 # ... # 分布式序列算法配置 keyGenerators: generate-algorithm-name> (+): # 分布式序列算法名称 type: # 分布式序列算法类型 props: # 分布式序列算法属性配置 # ... 操作步骤 1. 在 YAML t_order_inline: type: INLINE props: algorithm-expression: # INLINE 表达式 keyGenerators: generate-algorithm-name> (+): # 分布式序列算法名称 type: # 分布式序列算法类型 props: # 分布式序列算法属性配置 - !READWRITE_SPLITTING shardingsphere.rules.sharding.tables..key-generate-strategy. column= # 分布式序列列名称 spring.shardingsphere.rules.sharding.tables..key-generate-strategy.key- generator-name= # 分布式序列算法名称 spring

avg_state, sfunc = avg_transfn, finalfunc = avg_finalfn) CREATE TABLE agg_data_2k AS SELECT g FROM generate_series(0, 1999) g; CREATE SCHEMA alt_nsp1; ALTER AGGREGATE alt_agg3(int) OWNER TO regress_alter_generic_user2; avg_state, sfunc = avg_transfn, finalfunc = avg_finalfn) CREATE TABLE agg_data_2k AS SELECT g FROM generate_series(0, 1999) g; CREATE SCHEMA alt_nsp1; ALTER AGGREGATE alt_agg3(int) OWNER TO regress_alter_generic_user2; ame> (+): # 分片算法名称 type: # 分片算法类型 props: # 分片算法属性配置 # ... # 分布式序列算法配置 keyGenerators: generate-algorithm-name> (+): # 分布式序列算法名称 type: # 分布式序列算法类型 props: # 分布式序列算法属性配置 # ... 5.1. ShardingSphere-JDBC