@GeneratedValue generated way. this field will use generator named " �→ player_id" * @SequenceGenerator using `sequence` feature to create a generator, * and it named "player_jpa_id_seq" in database, initial default), and every operator will increase 1 (by ` �→ allocationSize`) */ @Id @GeneratedValue(generator="player_id") @SequenceGenerator(name="player_id", sequenceName="player_jpa_id_seq", �→ allocationSize=1) and should not be set manually. The attribute generator is used to specify the name of the generator as player_id. • @SequenceGenerator declares a generator that uses sequence, and uses the annotation attribute

* @GeneratedValue generated way. this field will use generator named "player_id" * @SequenceGenerator using `sequence` feature to create a generator, * and it named "player_jpa_id_seq" in database, initial parameter default), and every operator will increase 1 (by `allocationSize`) */ @Id @GeneratedValue(generator="player_id") @SequenceGenerator(name="player_id", sequenceName="player_jpa_id_seq", allocationSize=1) 使用注解属性 name 将此实体类和表 player_jpa 关联。 • @Id 声明此属性关联表的主键列。 • @GeneratedValue 表示自动生成该列的值，而不应手动设置，使用属性 generator 指定生成器的名称为 player_id。 • @SequenceGenerator 声明一个使用序列的生成器，使用注解属性 name 声明生成器的名称为 player_id （与 @GeneratedValue

statistics feature can cache. The default value is1000. TiKV snap- �→ generator �→ -pool- �→ size Newly added The size of the snap- �→ generator �→ thread pool. The default value is 2. 35 Configuration file Apply thread pool and the Store thread pool #11159 – Support configuring the size of the snap-generator thread pool #11247 – Optimize the issue of global lock race that occurs when there are many files SESSION • Default value: 0 • Range: [0, 2147483647] • This variable is used to seed the random value generator used in the RAND() SQL function. • The behavior of this variable is MySQL compatible. 12.4.1.42

the more popular ones are Baidu’s uid-generator and Meituan’s leaf. This section uses uid-generator as an example. The 64-bit ID structure generated by uid-generator is as follows: | sign | delta seconds node id: 22 bits by default. Represents the machine ID, usually obtained from a centralized ID generator when the application process is started. Common centralized ID generators include auto-increment | Create tables with non-clustered indexes and set SHARD_ROW_ID_BIT. Use an appli- cation ID generator to generate the primary key IDs. | It can avoid data write hotspots, 1991 guarantee the performance

the more popular ones are Baidu’s uid-generator and Meituan’s leaf. This section uses uid-generator as an example. The 64-bit ID structure generated by uid-generator is as follows: | sign | delta seconds node id: 22 bits by default. Represents the machine ID, usually obtained from a centralized ID generator when the application process is started. Common centralized ID generators include auto-increment | Create tables with non-clustered indexes and set SHARD_ROW_ID_BIT. Use an appli- cation ID generator to generate the primary key IDs. | It can avoid data write hotspots, 2064 guarantee the performance

the more popular ones are Baidu’s uid-generator and Meituan’s leaf. This section uses uid-generator as an example. The 64-bit ID structure generated by uid-generator is as follows: | sign | delta seconds node id: 22 bits by default. Represents the machine ID, usually obtained from a centralized ID generator when the application process is started. Common centralized ID generators include auto-increment | Create tables with non-clustered indexes and set SHARD_ROW_ID_BIT. Use an appli- cation ID generator to generate the primary key IDs. | It can avoid data write hotspots, 2108 guarantee the performance

the more popular ones are Baidu’s uid-generator and Meituan’s leaf. This section uses uid-generator as an example. The 64-bit ID structure generated by uid-generator is as follows: | sign | delta seconds node id: 22 bits by default. Represents the machine ID, usually obtained from a centralized ID generator when the application process is started. Common centralized ID generators include auto-increment | Create tables with non-clustered indexes and set SHARD_ROW_ID_BIT. Use an appli- cation ID generator to generate the primary key IDs. | It can avoid data write hotspots, 2087 guarantee the performance

the more popular ones are Baidu’s uid-generator and Meituan’s leaf. This section uses uid-generator as an example. The 64-bit ID structure generated by uid-generator is as follows: | sign | delta seconds node id: 22 bits by default. Represents the machine ID, usually obtained from a centralized ID generator when the application process is started. Common centralized ID generators include auto-increment | Create tables with non-clustered indexes and set SHARD_ROW_ID_BIT. Use an appli- cation ID generator to generate the primary key IDs. | It can avoid data write hotspots, 2626 guarantee the performance

the more popular ones are Baidu’s uid-generator and Meituan’s leaf. This section uses uid-generator as an example. The 64-bit ID structure generated by uid-generator is as follows: | sign | delta seconds node id: 22 bits by default. Represents the machine ID, usually obtained from a centralized ID generator when the application process is started. Common centralized ID generators include auto-increment | Create tables with non-clustered indexes and set SHARD_ROW_ID_BIT. Use an appli- cation ID generator to generate the primary key IDs. | It can avoid data write hotspots, 2201 guarantee the performance

the more popular ones are Baidu’s uid-generator and Meituan’s leaf. This section uses uid-generator as an example. The 64-bit ID structure generated by uid-generator is as follows: | sign | delta seconds node id: 22 bits by default. Represents the machine ID, usually obtained from a centralized ID generator when the application process is started. Common centralized ID generators include auto-increment | Create tables with non-clustered indexes and set SHARD_ROW_ID_BIT. Use an appli- cation ID generator to generate the primary key IDs. | It can avoid data write hotspots, 2209 guarantee the performance