第67练 项目九 事件概述和创建事件《数据库原理与应用技术-MySQL》（河北科学技术出版社）一课一练（河北省）

编写说明：依托三阶支架资源编写方案，《一课一练》明确基础层具象化支架定位，作为课堂同步配套资源，其内容与课堂教学深度绑定，并且精准匹配中职学生知识基础与学习特质，遵循"由浅入深、循序渐进"的认知规律，聚焦基础性与实效性核心，通过拆解知识点、简化认知难度，切实降低学习门槛，为后续知识巩固与能力提升筑牢根基，是优质课后作业首选。 本卷是《数据库原理与应用技术-MySQL》（河北科学技术出版社）《一课一练》第67练，内容是事件概述和创建事件。 《数据库原理与应用技术-MySQL》（河北科学技术出版社）《一课一练》 第67练 事件概述和创建事件 一、单项选择题 1. 临时开启 MySQL 事件调度器，下列 SQL 语句语法完全正确的是（ ） A. SET event_scheduler=ON; B. SET GLOBAL event_scheduler=ON; C. SET SESSION event_scheduler=1; D. SET GLOBAL event_scheduler='ON'; 【答案】B 【解析】临时开启事件调度器必须使用SET GLOBAL（全局级别），不能省略或用SESSION；参数值ON/OFF或1/0均可，但不能加单引号（加引号会被识别为字符串，部分版本报错）。A 错误：缺少GLOBAL；C 错误：不能用SESSION；D 错误：ON加了单引号。 2.查询当前事件调度器的状态，下列写法正确的是（ ） A. SHOW VARIABLES event_scheduler; B. SHOW VARIABLES LIKE "event_scheduler"; C. SELECT event_scheduler; D. SHOW VARIABLES LIKE 'event_scheduler'; 【答案】D 3.创建一个单次执行的事件（2026 年 12 月 31 日 23:59:59 执行），下列语法正确的是（ ） A. CREATE EVENT IF NOT EXISTS e_single ON SCHEDULE AT 2026-12-31 23:59:59 DO TRUNCATE TABLE log; B. CREATE EVENT IF NOT EXISTS e_single ON SCHEDULE AT '2026-12-31 23:59:59' DO TRUNCATE TABLE log; C. CREATE EVENT IF NOT EXISTS e_single ON SCHEDULE EVERY '2026-12-31 23:59:59' DO TRUNCATE TABLE log; D. CREATE EVEVT IF NOT EXISTS e_single ON SCHEDULE AT '2026-12-31 23:59:59' DO TRUNCATE TABLE log; 【答案】B 【解析】单次事件用AT 时间戳，时间戳必须加单引号；关键字为EVENT（注意拼写）。A 错误：时间戳未加单引号；C 错误：EVERY用于重复事件，不能接固定时间戳；D 错误：EVENT拼写为EVEVT（拼写错误）。 4.创建一个每 1 小时执行一次的重复事件，下列语法正确的是（ ） A. CREATE EVENT e_hourly ON SCHEDULE EVERY 1 HOUR DO INSERT INTO stats(data) VALUES(NOW()); B. CREATE EVENT e_hourly ON SCHEDULE EVERY HOUR 1 DO INSERT INTO stats(data) VALUES(NOW()); C. CREATE EVENT e_hourly ON SCHEDULE EVERY 1 HOURS DO INSERT INTO stats(data) VALUES(NOW()); D. CREATE EVENT e_hourly ON SCHEDULE EVERY 1 HOUR STARTS 2026-05-04 00:00:00 DO INSERT INTO stats(data) VALUES(NOW()); 【答案】A 【解析】重复事件语法为EVERY 数量 时间单位（时间单位用单数：YEAR/MONTH/DAY/HOUR/MINUTE/SECOND）；STARTS后的时间戳必须加单引号。B 错误：数量和时间单位顺序颠倒；C 错误：时间单位用了复数HOURS；D 错误：STARTS后的时间戳未加单引号。 5.创建事件时要求 “执行完毕后保留事件”，下列参数写法正确的是（ ） A. CREATE EVENT e_daily ON SCHEDULE EVERY 1 DAY ON PRESERVE COMPLETION DO DELETE FROM log WHERE create_time < NOW()-INTERVAL 7 DAY; B. CREATE EVENT e_daily ON SCHEDULE EVERY 1 DAY ON COMPLETION PRESERVE DO DELETE FROM log WHERE create_time < NOW()-INTERVAL 7 DAY; C. CREATE EVENT e_daily ON SCHEDULE EVERY 1 DAY ON COMPLETION NOT PRESERVE DO DELETE FROM log WHERE create_time < NOW()-INTERVAL 7 DAY; D. CREATE EVENT e_daily ON SCHEDULE EVERY 1 DAY PRESERVE ON COMPLETION DO DELETE FROM log WHERE create_time < NOW()-INTERVAL 7 DAY; 【答案】B 【解析】保留事件的标准参数为ON COMPLETION PRESERVE（固定顺序，不能拆分或颠倒）；NOT PRESERVE为执行后删除（默认行为）。A 错误：PRESERVE和COMPLETION顺序颠倒；C 错误：NOT PRESERVE会删除事件；D 错误：参数顺序完全错误。 6.创建事件时设置 “事件创建后暂不执行，后续手动启用”，下列状态参数写法正确的是（ ） A. CREATE EVENT e_weekly ON SCHEDULE EVERY 1 WEEK ON COMPLETION PRESERVE ENABLED DO UPDATE goods SET stock=stock+100 WHERE g_id=1; B. CREATE EVENT e_weekly ON SCHEDULE EVERY 1 WEEK ON COMPLETION PRESERVE DISABLED DO UPDATE goods SET stock=stock+100 WHERE g_id=1; C. CREATE EVENT e_weekly ON SCHEDULE EVERY 1 WEEK ON COMPLETION PRESERVE DISABLE DO UPDATE goods SET stock=stock+100 WHERE g_id=1; D. CREATE EVENT e_weekly ON SCHEDULE EVERY 1 WEEK DISABLE ON COMPLETION PRESERVE DO UPDATE goods SET stock=stock+100 WHERE g_id=1; 【答案】C 7.为事件添加注释 “每月 1 号凌晨 1 点统计上月销量”，下列 COMMENT 参数写法正确的是（ ） A. CREATE EVENT e_monthly ON SCHEDULE EVERY 1 MONTH STARTS '2026-06-01 01:00:00' ON COMPLETION PRESERVE COMMENT '每月1号凌晨1点统计上月销量' DO INSERT INTO sales_report(month,total) SELECT DATE_FORMAT(NOW()-INTERVAL 1 MONTH,'%Y-%m'),SUM(amount) FROM sale; B. CREATE EVENT e_monthly ON SCHEDULE EVERY 1 MONTH STARTS '2026-06-01 01:00:00' ON COMPLETION PRESERVE COMMENT 每月1号凌晨1点统计上月销量 DO INSERT INTO sales_report(month,total) SELECT DATE_FORMAT(NOW()-INTERVAL 1 MONTH,'%Y-%m'),SUM(amount) FROM sale; C. CREATE EVENT e_monthly ON SCHEDULE EVERY 1 MONTH STARTS '2026-06-01 01:00:00' ON COMPLETION PRESERVE COMMENT='每月1号凌晨1点统计上月销量' DO INSERT INTO sales_report(month,total) SELECT DATE_FORMAT(NOW()-INTERVAL 1 MONTH,'%Y-%m'),SUM(amount) FROM sale; D. CREATE EVENT e_monthly ON SCHEDULE EVERY 1 MONTH STARTS '2026-06-01 01:00:00' ON COMPLETION PRESERVE COMMENT "每月1号凌晨1点统计上月销量" DO INSERT INTO sales_report(month,total) SELECT DATE_FORMAT(NOW()-INTERVAL 1 MONTH,'%Y-%m'),SUM(amount) FROM sale; 【答案】A 【解析】COMMENT参数语法为COMMENT '注释内容'（注释必须加单引号，不能加等号，不能用双引号）。B 错误：注释未加单引号；C 错误：COMMENT后多了等号；D 错误：注释用了双引号。 8.事件主体包含多条 SQL 语句，下列写法正确的是（ ） A. CREATE EVENT e_multi ON SCHEDULE EVERY 1 DAY ON COMPLETION PRESERVE DO INSERT INTO operate_log(op_type,op_time) VALUES('每日统计',NOW()); UPDATE stats SET total=total+1 WHERE stat_date=CURDATE(); B. CREATE EVENT e_multi ON SCHEDULE EVERY 1 DAY ON COMPLETION PRESERVE DO BEGIN INSERT INTO operate_log(op_type,op_time) VALUES('每日统计',NOW()); UPDATE stats SET total=total+1 WHERE stat_date=CURDATE(); END; C. CREATE EVENT e_multi ON SCHEDULE EVERY 1 DAY ON COMPLETION PRESERVE DO ( INSERT INTO operate_log(op_type,op_time) VALUES('每日统计',NOW()); UPDATE stats SET total=total+1 WHERE stat_date=CURDATE(); ); D. CREATE EVENT e_multi ON SCHEDULE EVERY 1 DAY ON COMPLETION PRESERVE DO BEGIN INSERT INTO operate_log(op_type,op_time) VALUES('每日统计',NOW()) UPDATE stats SET total=total+1 WHERE stat_date=CURDATE() END; 【答案】B 【解析】事件主体包含多条语句时，必须用BEGIN...END复合语句包裹；每条 SQL 语句末尾必须加分号 。A 错误：多条语句未用BEGIN...END包裹；C 错误：用小括号代替BEGIN...END（语法错误）；D 错误：两条 SQL 语句末尾未加分号。 9.临时关闭 MySQL 事件调度器，下列 SQL 语句语法完全正确的是（ ） A. SET GLOBAL event_scheduler=0; B. SET event_scheduler=OFF; C. SET GLOBAL event_scheduler='OFF'; D. SET @@event_scheduler=0; 【答案】A 【解析】临时关闭事件调度器必须用SET GLOBAL（或SET @@global.event_scheduler），参数值OFF/0均可，不能加单引号。B 错误：缺少GLOBAL；C 错误：OFF加了单引号；D 错误：缺少global（@@event_scheduler为会话级别，不能关闭全局调度器）。 10.下列语句完全正确的是（ ） A. CREATE EVENT IF NOT EXISTS e_daily_clean ON SCHEDULE EVERY 1 DAY STARTS '2026-05-04 02:00:00' ON COMPLETION PRESERVE ENABLE COMMENT '每日凌晨2点清理7天前的日志' DO BEGIN DELETE FROM access_log WHERE create_time < NOW()-INTERVAL 7 DAY; INSERT INTO clean_log(clean_time,delete_count) VALUES(NOW(),ROW_COUNT()); END; B. CREATE EVENT IF NOT EXISTS e_daily_clean ON SCHEDULE EVERY 1 DAY STARTS '2026-05-04 02:00:00' ENABLE ON COMPLETION PRESERVE COMMENT '每日凌晨2点清理7天前的日志' DO BEGIN DELETE FROM access_log WHERE create_time < NOW()-INTERVAL 7 DAY; INSERT INTO clean_log(clean_time,delete_count) VALUES(NOW(),ROW_COUNT()); END; C. CREATE EVENT IF NOT EXISTS e_daily_clean ON SCHEDULE EVERY 1 DAY STARTS 2026-05-04 02:00:00 ON COMPLETION PRESERVE ENABLE COMMENT '每日凌晨2点清理7天前的日志' DO DELETE FROM access_log WHERE create_time < NOW()-INTERVAL 7 DAY; INSERT INTO clean_log(clean_time,delete_count) VALUES(NOW(),ROW_COUNT()); D. CREATE EVENT IF NOT EXISTS e_daily_clean ON SCHEDULE EVERY 1 DAY STARTS '2026-05-04 02:00:00' ON COMPLETION PRESERVE ENABLED COMMENT='每日凌晨2点清理7天前的日志' DO BEGIN DELETE FROM access_log WHERE create_time < NOW()-INTERVAL 7 DAY; INSERT INTO clean_log(clean_time,delete_count) VALUES(NOW(),ROW_COUNT()); END; 【答案】A 原创精品资源学科网独家享有版权，侵权必究！ 学科网（北京）股份有限公司 $ 编写说明：依托三阶支架资源编写方案，《一课一练》明确基础层具象化支架定位，作为课堂同步配套资源，其内容与课堂教学深度绑定，并且精准匹配中职学生知识基础与学习特质，遵循"由浅入深、循序渐进"的认知规律，聚焦基础性与实效性核心，通过拆解知识点、简化认知难度，切实降低学习门槛，为后续知识巩固与能力提升筑牢根基，是优质课后作业首选。 本卷是《数据库原理与应用技术-MySQL》（河北科学技术出版社）《一课一练》第67练，内容是事件概述和创建事件。 《数据库原理与应用技术-MySQL》（河北科学技术出版社）《一课一练》 第67练 事件概述和创建事件 一、单项选择题 1. 临时开启 MySQL 事件调度器，下列 SQL 语句语法完全正确的是（ ） A. SET event_scheduler=ON; B. SET GLOBAL event_scheduler=ON; C. SET SESSION event_scheduler=1; D. SET GLOBAL event_scheduler='ON'; 2.查询当前事件调度器的状态，下列写法正确的是（ ） A. SHOW VARIABLES event_scheduler; B. SHOW VARIABLES LIKE "event_scheduler"; C. SELECT event_scheduler; D. SHOW VARIABLES LIKE 'event_scheduler'; 3.创建一个单次执行的事件（2026 年 12 月 31 日 23:59:59 执行），下列语法正确的是（ ） A. CREATE EVENT IF NOT EXISTS e_single ON SCHEDULE AT 2026-12-31 23:59:59 DO TRUNCATE TABLE log; B. CREATE EVENT IF NOT EXISTS e_single ON SCHEDULE AT '2026-12-31 23:59:59' DO TRUNCATE TABLE log; C. CREATE EVENT IF NOT EXISTS e_single ON SCHEDULE EVERY '2026-12-31 23:59:59' DO TRUNCATE TABLE log; D. CREATE EVEVT IF NOT EXISTS e_single ON SCHEDULE AT '2026-12-31 23:59:59' DO TRUNCATE TABLE log; 4.创建一个每 1 小时执行一次的重复事件，下列语法正确的是（ ） A. CREATE EVENT e_hourly ON SCHEDULE EVERY 1 HOUR DO INSERT INTO stats(data) VALUES(NOW()); B. CREATE EVENT e_hourly ON SCHEDULE EVERY HOUR 1 DO INSERT INTO stats(data) VALUES(NOW()); C. CREATE EVENT e_hourly ON SCHEDULE EVERY 1 HOURS DO INSERT INTO stats(data) VALUES(NOW()); D. CREATE EVENT e_hourly ON SCHEDULE EVERY 1 HOUR STARTS 2026-05-04 00:00:00 DO INSERT INTO stats(data) VALUES(NOW()); 5.创建事件时要求 “执行完毕后保留事件”，下列参数写法正确的是（ ） A. CREATE EVENT e_daily ON SCHEDULE EVERY 1 DAY ON PRESERVE COMPLETION DO DELETE FROM log WHERE create_time < NOW()-INTERVAL 7 DAY; B. CREATE EVENT e_daily ON SCHEDULE EVERY 1 DAY ON COMPLETION PRESERVE DO DELETE FROM log WHERE create_time < NOW()-INTERVAL 7 DAY; C. CREATE EVENT e_daily ON SCHEDULE EVERY 1 DAY ON COMPLETION NOT PRESERVE DO DELETE FROM log WHERE create_time < NOW()-INTERVAL 7 DAY; D. CREATE EVENT e_daily ON SCHEDULE EVERY 1 DAY PRESERVE ON COMPLETION DO DELETE FROM log WHERE create_time < NOW()-INTERVAL 7 DAY; 6.创建事件时设置 “事件创建后暂不执行，后续手动启用”，下列状态参数写法正确的是（ ） A. CREATE EVENT e_weekly ON SCHEDULE EVERY 1 WEEK ON COMPLETION PRESERVE ENABLED DO UPDATE goods SET stock=stock+100 WHERE g_id=1; B. CREATE EVENT e_weekly ON SCHEDULE EVERY 1 WEEK ON COMPLETION PRESERVE DISABLED DO UPDATE goods SET stock=stock+100 WHERE g_id=1; C. CREATE EVENT e_weekly ON SCHEDULE EVERY 1 WEEK ON COMPLETION PRESERVE DISABLE DO UPDATE goods SET stock=stock+100 WHERE g_id=1; D. CREATE EVENT e_weekly ON SCHEDULE EVERY 1 WEEK DISABLE ON COMPLETION PRESERVE DO UPDATE goods SET stock=stock+100 WHERE g_id=1; 7.为事件添加注释 “每月 1 号凌晨 1 点统计上月销量”，下列 COMMENT 参数写法正确的是（ ） A. CREATE EVENT e_monthly ON SCHEDULE EVERY 1 MONTH STARTS '2026-06-01 01:00:00' ON COMPLETION PRESERVE COMMENT '每月1号凌晨1点统计上月销量' DO INSERT INTO sales_report(month,total) SELECT DATE_FORMAT(NOW()-INTERVAL 1 MONTH,'%Y-%m'),SUM(amount) FROM sale; B. CREATE EVENT e_monthly ON SCHEDULE EVERY 1 MONTH STARTS '2026-06-01 01:00:00' ON COMPLETION PRESERVE COMMENT 每月1号凌晨1点统计上月销量 DO INSERT INTO sales_report(month,total) SELECT DATE_FORMAT(NOW()-INTERVAL 1 MONTH,'%Y-%m'),SUM(amount) FROM sale; C. CREATE EVENT e_monthly ON SCHEDULE EVERY 1 MONTH STARTS '2026-06-01 01:00:00' ON COMPLETION PRESERVE COMMENT='每月1号凌晨1点统计上月销量' DO INSERT INTO sales_report(month,total) SELECT DATE_FORMAT(NOW()-INTERVAL 1 MONTH,'%Y-%m'),SUM(amount) FROM sale; D. CREATE EVENT e_monthly ON SCHEDULE EVERY 1 MONTH STARTS '2026-06-01 01:00:00' ON COMPLETION PRESERVE COMMENT "每月1号凌晨1点统计上月销量" DO INSERT INTO sales_report(month,total) SELECT DATE_FORMAT(NOW()-INTERVAL 1 MONTH,'%Y-%m'),SUM(amount) FROM sale; 8.事件主体包含多条 SQL 语句，下列写法正确的是（ ） A. CREATE EVENT e_multi ON SCHEDULE EVERY 1 DAY ON COMPLETION PRESERVE DO INSERT INTO operate_log(op_type,op_time) VALUES('每日统计',NOW()); UPDATE stats SET total=total+1 WHERE stat_date=CURDATE(); B. CREATE EVENT e_multi ON SCHEDULE EVERY 1 DAY ON COMPLETION PRESERVE DO BEGIN INSERT INTO operate_log(op_type,op_time) VALUES('每日统计',NOW()); UPDATE stats SET total=total+1 WHERE stat_date=CURDATE(); END; C. CREATE EVENT e_multi ON SCHEDULE EVERY 1 DAY ON COMPLETION PRESERVE DO ( INSERT INTO operate_log(op_type,op_time) VALUES('每日统计',NOW()); UPDATE stats SET total=total+1 WHERE stat_date=CURDATE(); ); D. CREATE EVENT e_multi ON SCHEDULE EVERY 1 DAY ON COMPLETION PRESERVE DO BEGIN INSERT INTO operate_log(op_type,op_time) VALUES('每日统计',NOW()) UPDATE stats SET total=total+1 WHERE stat_date=CURDATE() END; 9.临时关闭 MySQL 事件调度器，下列 SQL 语句语法完全正确的是（ ） A. SET GLOBAL event_scheduler=0; B. SET event_scheduler=OFF; C. SET GLOBAL event_scheduler='OFF'; D. SET @@event_scheduler=0; 10.下列语句完全正确的是（ ） A. CREATE EVENT IF NOT EXISTS e_daily_clean ON SCHEDULE EVERY 1 DAY STARTS '2026-05-04 02:00:00' ON COMPLETION PRESERVE ENABLE COMMENT '每日凌晨2点清理7天前的日志' DO BEGIN DELETE FROM access_log WHERE create_time < NOW()-INTERVAL 7 DAY; INSERT INTO clean_log(clean_time,delete_count) VALUES(NOW(),ROW_COUNT()); END; B. CREATE EVENT IF NOT EXISTS e_daily_clean ON SCHEDULE EVERY 1 DAY STARTS '2026-05-04 02:00:00' ENABLE ON COMPLETION PRESERVE COMMENT '每日凌晨2点清理7天前的日志' DO BEGIN DELETE FROM access_log WHERE create_time < NOW()-INTERVAL 7 DAY; INSERT INTO clean_log(clean_time,delete_count) VALUES(NOW(),ROW_COUNT()); END; C. CREATE EVENT IF NOT EXISTS e_daily_clean ON SCHEDULE EVERY 1 DAY STARTS 2026-05-04 02:00:00 ON COMPLETION PRESERVE ENABLE COMMENT '每日凌晨2点清理7天前的日志' DO DELETE FROM access_log WHERE create_time < NOW()-INTERVAL 7 DAY; INSERT INTO clean_log(clean_time,delete_count) VALUES(NOW(),ROW_COUNT()); D. CREATE EVENT IF NOT EXISTS e_daily_clean ON SCHEDULE EVERY 1 DAY STARTS '2026-05-04 02:00:00' ON COMPLETION PRESERVE ENABLED COMMENT='每日凌晨2点清理7天前的日志' DO BEGIN DELETE FROM access_log WHERE create_time < NOW()-INTERVAL 7 DAY; INSERT INTO clean_log(clean_time,delete_count) VALUES(NOW(),ROW_COUNT()); END; 原创精品资源学科网独家享有版权，侵权必究！ 学科网（北京）股份有限公司 $