该功能允许您将不同实例作为外部数据源做...a|b|c-+-+-2|12|t1 3|13|t1 4|14|t1 7|17|t1 8|18|t1 1|11|t1 5|15|t1 6|16|t1 9|19|t1 10|20|t1(10 rows)相关文档 跨库查询：如果您的数据存储在同一实例的不同数据库，可以实现跨库的联合查询。
a CTE statement is in the following format:WITH x1 AS(SELECT a FROM t1),x2 AS(SELECT b FROM t1)SELECT*FROM x1 JOIN x2 ON x1.a=x2.b;The following methods are available for optimizing CTE statements:MATERIALIZED:computes the...
float8 ST_nearestApproachDistance(trajectory traj,trajectory traj2,timestamp t1,timestamp t2);参数 参数名称 描述 traj1 轨迹对象1。traj2 轨迹对象2。t1 开始时间。t2 结束时间。range 时间段。示例 Select ST_...
float8 ST_nearestApproachDistance(trajectory traj,trajectory traj2,timestamp t1,timestamp t2);参数 参数名称 描述 traj1 轨迹对象1。traj2 轨迹对象2。t1 开始时间。t2 结束时间。range 时间段。示例 Select ST_...
float8 ST_nearestApproachDistance(trajectory traj,trajectory traj2,timestamp t1,timestamp t2);参数 参数名称 描述 traj1 轨迹对象1。traj2 轨迹对象2。t1 开始时间。t2 结束时间。range 时间段。示例 Select ST_...
and five delta files are generated.The compaction operation is performed at the time points t2 and t4,and two base files b1 and b2 are generated.In this example,if the value in the Begin column is t1-1 and the value in the...
setosa 4.4 2 Iris-setosa 4.5 Sql compiled:CREATE TABLE tmp_pyodps_bc0917bb_f10c_426b_9b75_47e94478382a LIFECYCLE 1 AS SELECT t2.`name` FROM(SELECT DISTINCT t1.`name` FROM WB_BestPractice_dev.`pyodps_iris` t1)t2 Instance ID...
Execute the following statement.The query result is 2,'2',4.0.SELECT sb1,sb2,sb3 FROM(SELECT s1 AS sb1,s2 AS sb2,s3*2 AS sb3 FROM t1)AS sb WHERE sb1 1;Query the average value of grouped data processed by the SUM function....
Parameters Parameter Description traj1 Trajectory object 1.traj2 Trajectory object 2.t1 The start time.t2 The end time.range The time range.Examples Select ST_intersection((Select traj from traj_table where id=1),(Select ...
This function returns the nearest distance between trajectory objects 1 and 2 within the specified time range.Syntax float8 ST_nearestApproachDistance(trajectory traj,trajectory traj2);float8 ST_nearestApproachDistance...
Parameters Parameter Description traj1 Trajectory object 1.traj2 Trajectory object 2.t1 The start time.t2 The end time.range The time range.Examples Select ST_intersection((Select traj from traj_table where id=1),(Select ...
Parameters Parameter Description traj1 Trajectory object 1.traj2 Trajectory object 2.t1 The start time.t2 The end time.range The time range.Examples Select ST_intersection((Select traj from traj_table where id=1),(Select ...
Problem description When I use the same auto-increment primary key value(auto-increment ID)to query data from the primary and secondary ...INSERT INTO t2 SELECT*FROM t1 ORDER BY col1,col2;DROP TABLE t1;RENAME TABLE t2 TO t1;
Problem description When I use the same auto-increment primary key value(auto-increment ID)to query data from the primary and secondary ...INSERT INTO t2 SELECT*FROM t1 ORDER BY col1,col2;DROP TABLE t1;RENAME TABLE t2 TO t1;
a|b|c-+-+-2|12|t1 3|13|t1 4|14|t1 7|17|t1 8|18|t1 1|11|t1 5|15|t1 6|16|t1 9|19|t1 10|20|t1(10 rows)性能测试 以下内容为跨实例查询的TPC-H性能测试，测试数据量为1 TB，并分别在数据库本地和目标端数据库中执行查询。大数据场景...
The Table Scan operator scans the t1 and t2 tables.The Redistribute Motion operator redistributes the data of the t1 and t2 tables based on the hash values of their b columns to compute nodes.The Hash operator creates a ...
t2.brand,t1.groupid,t3.tag1,t3.tag2,t3.tag3,.count(1)as cnt,array_agg(uid)as uids,hll_add_agg(hll_hash_integer(uid))as hll_uids from t1,t2,t3 where t1.uid=t3.uid and t1.uid=t2.uid group by t1.day,t2.brand,t1.groupid,...
{{queryConversation.data}} querySession SELECT t1.session_id,t1.content,t1.create_at FROM chat_session t1 INNER JOIN(SELECT session_id,MIN(create_at)as min_create_at FROM chat_session GROUP BY session_id)t2 ON t1.session_...
t1 INNER JOIN t2 and t2 INNER JOIN t1 are equivalent query plans.The query optimizer can turn t1 INNER JOIN t2 into t2 INNER JOIN t1 by transforming equivalent query plans.This transformation by the optimizer is called a ...
CTE ON t2.i1=T_CTE.i1_cte AND t2.i2=T_CTE.i2_cte You can also use a CTE in a JOIN clause:WITH T_CTE(i1_cte,i2_cte)AS(SELECT i1,i2 FROM t1)SELECT*FROM t2 WHERE EXISTS(SELECT*FROM T_CTE WHERE t2.i1=i1_cte AND t2.i2=i2_cte)Or...
STRUCT的结构为 {f1,T1,f2,T2[,.]}，f1、f2 代表成员变量，T1、T2 分别代表成员变量 f1、f2 的取值。fieldName：必填。STRING类型。STRUCT类型对象的成员变量。返回值说明 返回STRUCT类型对象的成员变量的取值。使用示例-返回hello。select...
sorts the join operations,the join operation that is performed on the t2 and l2 tables is pushed down to the LogicalView operator.EXPLAIN select t2.id from t2 join t1 on t2.id=t1.id join l2 on t1.id=l2.id;Project(id="id")...
segments:6)-Append-Hash Join Hash Cond:(t2_p1.id=t3_p1.id)-Partial Seq Scan on t2_p1-Hash-Full Seq Scan on t3_p1-Hash Join Hash Cond:(t2_p2.id=t3_p2.id)-Partial Seq Scan on t2_p2-Hash-Full Seq Scan on t3_p2-Hash Join Hash ...
CTE(i1_cte,i2_cte)AS(SELECT i1,i2 FROM t1)SELECT*FROM t2 JOIN T_CTE ON t2.i1=T_CTE.i1_cte AND t2.i2=T_CTE.i2_cte In the preceding sample code,a CTE is used in the JOIN clause.WITH T_CTE(i1_cte,i2_cte)AS(SELECT i1,i2 FROM t...
本数据库为每个收到查询产生一个 查询计划。选择正确的计划来匹配查询结构和数据的属性...让我们尝试连接两个表，使用我们已经讨论过的列：EXPLAIN SELECT*FROM tenk1 t1,tenk2 t2 WHERE t1.unique1 10 AND t1.unique2=t2.unique2;QUERY PLAN-...
命令格式 inline(array struct f1:T1,f2:T2[,.])参数说明 f1:T1、f2:T2：必填。可以为任意类型。f1、f2 代表成员变量，T1、T2 分别代表成员变量 f1、f2 的取值。返回值说明 返回STRUCT数组展开的数据。使用示例 例如表 t_table 的字段为 t_...
The data file name is t1.CSV.The name of the original data file-Any number.CSV.Example:If the name of the original data file is t1.CSV,the split data files are called t1.CSV,t1-1.CSV,and t1-2.CSV.Upload split data files....
name Yes The name of the materialized view that you want to create.days No The lifecycle of the materialized view that you want to create.Unit:days.Valid values:1 to 37231.BUILD DEFERRED No If this keyword is added,only ...
Create a partitioned materialized view.CREATE MATERIALIZED VIEW mv LIFECYCLE 7 PARTITIONED BY(ds)AS SELECT t1.id,t1.ds AS ds FROM t1 JOIN t2 ON t1.id=t2.id;The following table shows the comparison between the original ...
Level|Code|Message|+-+-+-+|Note|1003|/*select#1*/select `v`.`c1` AS `c1` from(/*select#3*/select `testdb`.`t1`.`c1` AS `c1`,`testdb`.`t1`.`c2` AS `c2` from `testdb`.`t1` group by `testdb`.`t1`.`c1`,`testdb`.`t1`.`c2`)`v`|+...
num|name|num|value-+-+-+-1|a|1|xxx 1|a|3|yyy 1|a|5|zzz 2|b|1|xxx 2|b|3|yyy 2|b|5|zzz 3|c|1|xxx 3|c|3|yyy 3|c|5|zzz(9 rows)=SELECT*FROM t1 INNER JOIN t2 ON t1.num=t2.num;num|name|num|value-+-+-+-1|a|1|xxx 3|c|3|yyy(2 rows)=...
outln.add_index_outline('outline_db','',1,'USE INDEX','ind_1','',"SELECT*FROM t1 WHERE t1.col1=1 AND t1.col2='xpchild'");preview_outline Syntax dbms_outln.preview_outline(' Schema_name ',' Query ');Examples mysql CALL dbms...