MySQL内置了RAND()函数,该函数返回0到1之间的随机数。我们可以通过以下方法将其转换为指定范围的随机整数: SELECT FLOOR(RAND() * (max - min + 1)) + min AS random_number; 1. 其中,min和max分别是需要生成的随机整数的最小值和最大值。 下面是一个生成1到100之间随机整数的示例: SE
RANDOM_BYTES(len) This function returns a binary string oflenrandom bytes generated using the random number generator of the SSL library. Permitted values oflenrange from 1 to 1024. For values outside that range, an error occurs. ReturnsNULLiflenisNULL. ...
Multiple hosts are separated by commas and a priority (0 to 100), if provided, determines the host selection order. As of Connector/NET 8.0.19, host selection is random when priorities are omitted or are the same for each host. // Selects the host with the highest priority (100) ...
sysbench --test=oltp help --oltp-test-mode=STRING 测试类型:simple(简单select测试),complex(事务测试),nontrx(非事务测试),sp(存储过程) ;默认complex --oltp-reconnect-mode=STRING 连接类型:session(每个线程到测试结束不重新连接),transaction(执行每个事务重新连接),query(每一个查询重新连接),random(随机)...
SELECT generate_series(1,5) AS numbers; -- 生成1-5的数组 -- 结合数组生成测试数据 INSERT INTO test_table (id, values) SELECT g, ARRAY(SELECT random() *100FROMgenerate_series(1,10))FROMgenerate_series(1,5) g; 数组排序与去重 -- 数组元素排序 ...
Possible values are full and decorrelated, or you can also specify your own algorithm. See Connection Backoff for more information. full base Integer Number of milliseconds added to random backoff values. 2 cap Integer Maximum number of milliseconds between connection retries. 100 config Object A ...
sudo sh -c "echo 4096 > /sys/class/net/eth0/queues/rx-1/rps_flow_cnt" 其中:ffffffff表示使用32个CPU(1个f表示4个CPU)。请根据实际配置修改,例如ECS为8核CPU,则输入ff。 常规命令行语法和选项。sysbench --help 以下命令可以输出各个检测项的帮助文档 ...
一些 page 在 buffer pool 中发现时,Innodb 会将该 extent 中的剩余 page 一并读到 buffer pool中,由于随机预读方式给 Innodb code 带来了一些不必要的复杂性,同时在性能也存在不稳定性,在5.5中已经将这种预读方式废弃。要启用此功能,请将配置变量设置 innodb_randomread_ahead 为ON。 3、索引维护 插入新...
oltp_delete.lua oltp_read_only.lua oltp_update_non_index.lua select_random_ranges.lua 除了oltp_common.lua是个公共模块,其它每个 lua 脚本都对应一个测试场景。 sysbench 用法讲解 sysbench 命令语法如下: sysbench [options]... [testname] [command] ...
(0..64) innodb_random_read_ahead =OFF # OFF #---innodb buffer pool state innodb_buffer_pool_dump_pct =25 # 25 innodb_buffer_pool_dump_at_shutdown =ON # ON innodb_buffer_pool_load_at_startup =ON # ON ### for performance_schema performance_schema =on # on performance_schema_consum...