Returns the maximum value in the group of the same data type. It ignores the NULL values. Get Maximum Value in the Column The following query fetches the maximumSalaryfrom theEmployeetable. Example: MAX() Copy SELECTMAX(Salary)AS MaxSalFROMEmployee; To check the above result, use the follow...
执行SHOW PROFILES 查出Query_ID后在执行 show profile for query Query_ID ,或者是show processlist,查看查询所耗时资源 得知查询到语句耗时主要集中在 sending data上 解决步骤: 1、查询资料需要开启查询缓存,执行命令查看开启情况 show variables like '%query_cache%',No则是未开启,改配置文件设置 query_cache_ty...
name) values(8, "Tom"),(8, "David"), (10, "Andy"); Query OK, 3 rows affected (0.00 sec) Records: 3 Duplicates: 0 Warnings: 0 mysql> select * from t_index; +---+---+---+ | id | age | name | +---+-
LEAD(value) OVER (ORDER BY name) as next_value FROM my_table;3
a | # create a stream for the pageviews topic : ksql> CREATE STREAM pageviews WITH (KAFKA_TOPIC='pageviews', VALUE_FORMAT='AVRO'); # create a table for the users topic: ksql> CREATE TABLE users (id VARCHAR PRIMARY KEY) WITH (KAFKA_TOPIC='users', VALUE_FORMAT='AVRO'); ksql> set...
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Query Memory Objects (default) Value --- --- Grants 18 Waiting 2 Available 0 Current Max 103536 Future Max 97527 Physical Max 139137 Next Request 5752 Waiting For 8628 Cost 16 Timeout 401 Wait Time 2750 (11 rows affected) Small Query Memory Objects (default) Value --- ---...
Getter; /** * 聚合类型 枚举类 * * @author CL */ @Getter @AllArgsConstructor public enum AggregationType { COUNT("count", "统计"), MAX("max", "最大值"), MIN("min", "最小值"), AVG("avg", "平均值"), SUM("sum", "求和"), ; private final String value; private final String...
Enter valuefor1:87m3rru3sy2jtPLAN_HASH_VALUEAVG_ET_SECS---372156129125.965 统计库2中的执行情况如下,存在两个子执行计划,但是效率都不错。 代码语言:javascript 代码运行次数:0 运行 AI代码解释 Enter valuefor1:87m3rru3sy2jtPLAN_HASH_VALUEAVG_ET_SECS---690487836.0873721561291.989 我们就可以在执行计...
1.对查询进行转换 sqlToRelConverter.convertQuery(validatedSqlNode) 1. 2. 2)创建 PlannerQueryOperation new PlannerQueryOperation(relational.project()); 3、将 Operation 转换为 List<Transformation<?>> List 2)将 optimizedRelNodes 转换为 execGraph val execGraph = translateToExecNodeGraph(optimizedRelNode...