SQL性能问题

因此我们使用了SQLROW_NUMBER OVER WINDOW功能来实现去重语法。去重本质上是一种特殊的TopN。SELECT*FROM(SELECT*,ROW_NUMBER()OVER(PARTITION BY col1[,col2.]ORDER BY timeAttributeCol[asc|desc])AS rownum FROM table_name)WHERE ...

高性能Flink SQL优化技巧

因此我们使用了SQLROW_NUMBER OVER WINDOW功能来实现去重语法。去重本质上是一种特殊的TopN。SELECT*FROM(SELECT*,ROW_NUMBER()OVER(PARTITION BY col1[,col2.]ORDER BY timeAttributeCol[asc|desc])AS rownum FROM table_name)WHERE ...

Inventory Hint

ERROR HY000:The affected row number does not match that of user specified.PolarDB MySQL版 5.7和8.0版本 UPDATE/*+TARGET_AFFECT_ROW(1)*/T SET c=c-1 WHERE id=1;ERROR HY000:The affected row number does not match that of user ...

性能白皮书(Nexmark性能测试)

测试步骤 分别创建以下Queries作业,创建作业详情请参见 SQL作业开发。q0 CREATE TEMPORARY TABLE nexmark_table(event_type INT,person ROW,name VARCHAR,emailAddress VARCHAR,creditCard VARCHAR,city VARCHAR,state VARCHAR,dateTime ...

Top-N

select a,b,c from(select*,row_number()over(partition by a order by c)as rk from MyTable)where rk;输出rank number字段:rk,该修改属于完全兼容修改。select a,b,c,rk from(select*,row_number()over(partition by a order by c)as ...

Deduplication

select a,b,c from(select*,row_number()over(partition by a order by proctime asc)as rk from MyTable)where rk=1;新增输入字段:d,该修改属于完全兼容修改。select a,b,c,d from(select*,row_number()over(partition by a order by ...

SQL诊断

ERRCODE_E_R_E_READING_SQL_DATA_NOT_PERMITTED 没有外部表的读权限。check permission for foreign table scan failed:failed to check permission:MaxCompute error,Authorization Failed[4019],You have NO privilege 'odps:Select' on ...

窗口函数

grouped=iris.groupby('name')grouped.mutate(grouped.sepallength.cumsum(),grouped.sort('sepallength').row_number()).head(10)name sepallength_sum row_number 0 Iris-setosa 250.3 1 1 Iris-setosa 250.3 2 2 Iris-setosa 250.3 3 3 ...

ROW_NUMBER

命令格式 row_number()over([partition_clause][orderby_clause])命令说明 计算当前行在分区中的行号,从1开始递增。参数说明 请参见 windowing_definition。不允许包含 frame_clause。返回值说明 返回BIGINT类型。示例数据 为便于理解各...

SQL错误码(ODPS-01CCCCX)

FAILED:ODPS-0130071:[1,8]Semantic analysis exception-function or view 'row_number' cannot be resolved 产生原因:SQL语句中使用的内建函数名称有误或者未携带参数,导致MaxCompute处理失败。解决措施:检查函数名称和参数名称,并...

WINDOW关键字

SELECT deptno,ename,max(sal)OVER w2 AS max_sal,row_number()OVER w1 AS nums FROM emp WINDOW w1 AS(partition by deptno order by sal desc),w2 AS(partition by deptno);示例3:使用window语句在全局定义named window。WINDOW w1 AS...

CUME_DIST

具体的返回值等于 row_number_of_last_peer/partition_row_count,其中:row_number_of_last_peer 指当前行所属GROUP的最后一行数据的ROW_NUMBER窗口函数返回值,partition_row_count 为该行数据所属分区的数据行数。示例数据 为便于理解各...

Window Top-N

select a,b,c,window_start from(select*,row_number()over(partition by b,window_start,window_end order by c)as rk from(select a,sum(b)as b,max(c)as c,window_start,window_end from table(tumble(table MyTable,descriptor(ts),...

数据迁移服务隐藏列机制说明

如下所示:CREATE TABLE"table1"("S1"NVARCHAR2(2)NOT NULL,"S2"NVARCHAR2(20)DEFAULT '默认值字段',"OMS_OBJECT_NUMBER"NUMBER INVISIBLE,"OMS_RELATIVE_FNO"NUMBER INVISIBLE,"OMS_BLOCK_NUMBER"NUMBER INVISIBLE,"OMS_ROW_NUMBER"NUMBER...

基于Python连接池DBUtils的应用开发

conn.close()#查询单条记录 def select_row(self,sql):connection=self._connect()statement=None try:statement=connection.cursor()statement.execute(sql)row=statement.fetchone()return row except Exception as e:print(e)finally:...

DBMS_SQL

LAST_ROW_COUNT 函数 INTEGER 返回获取的累计行数。OPEN_CURSOR 函数 INTEGER 打开游标。PARSE(c,statement,language_flag)存储过程 N/A 解析语句。与Oracle版本的DBMS_SQL执行相比,PolarDB 的DBMS_SQL执行是部分执行。PolarDB 仅支持上述...

sql_firewall

4(1 row)sql_firewall.sql_firewall_stat 展示预警模式下的警告数量(sql_warning)和防火墙模式下的错误数量(sql_error)。select*from sql_firewall.sql_firewall_stat;sql_warning|sql_error-+-2|1(1 row)示例-预警模式 select*from ...

sql_firewall

4(1 row)sql_firewall.sql_firewall_stat 展示预警模式下的警告数量(sql_warning)和防火墙模式下的错误数量(sql_error)。select*from sql_firewall.sql_firewall_stat;sql_warning|sql_error-+-2|1(1 row)示例-预警模式 select*from ...

SQL相关

GROUP_NAME|DBKEY_NAME|START_TIME|EXECUTE_TIME|SQL_EXECUTE_TIME|GETLOCK_CONNECTION_TIME|CREATE_CONNECTION_TIME|AFFECT_ROW|SQL|+-+-+-+-+-+-+-+-+-+|TDDL5_00_GROUP|db218249098_sqa_zmf_tddl5_00_3309|2016-03-16 13:05:38|1057|...

SQL相关

GROUP_NAME|DBKEY_NAME|START_TIME|EXECUTE_TIME|SQL_EXECUTE_TIME|GETLOCK_CONNECTION_TIME|CREATE_CONNECTION_TIME|AFFECT_ROW|SQL|+-+-+-+-+-+-+-+-+-+|TDDL5_00_GROUP|db218249098_sqa_zmf_tddl5_00_3309|2016-03-16 13:05:38|1057|...

SQL防火墙(sql_firewall)

4(1 row)sql_firewall.sql_firewall_stat 展示预警模式下的警告数量(sql_warning)和防火墙模式下的错误数量(sql_error)。postgres=select*from sql_firewall.sql_firewall_stat;sql_warning|sql_error-+-2|1(1 row)示例-预警模式 ...

应用程序连接示例

Select metadata/Select row count from delete Console.WriteLine("Deleted rows:"+row_count+"");Select column names from table sqlQuery="SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME='dbo.tb_test';cmd=...

从RDS同步至MaxCompute

insert overwrite table customer_1565944878 select id,register_time,address from(select row_number()over(partition by t.id order by record_id desc,after_flag desc)as row_number,record_id,operation_flag,after_flag,id,...

从RDS同步至MaxCompute

insert overwrite table<result_storage_table>select,,<colN>from(select row_number()over(partition by t.<primary_key_column>order by record_id desc,after_flag desc)as row_number,record_id,operation_flag,after_flag,,,<colN>...

Quick BI如何获取top10数据

area,province,sum(order_number)as order_num,row_number()over(partition by year(report_date),area order by sum(order_number)desc)as rank_num from company_sales_record group by year(report_date),area,province)a where rank_...

PolarDB-X 2.0同步至MaxCompute

并且binlog_row_image为full。否则预检查阶段提示报错,且无法成功启动数据同步任务。如为增量同步任务,DTS要求源数据库的本地Binlog日志保存24小时以上,如为全量同步和增量同步任务,DTS要求源数据库的本地Binlog日志至少保留7天以上...

SQL调优

SELECT RANK()OVER(PARTITION BY A ORDER BY B desc)AS RANK,ROW_NUMBER()OVER(PARTITION BY A ORDER BY B desc)AS row_num FROM MyTable;子查询优化 子查询如下所示。SELECT*FROM table_a a WHERE a.col1 IN(SELECT col1 FROM table_b b ...

在程序中通过AnalyticDB MySQL版Client高效写入数据到...

AdbClientException错误码 错误码名 错误码值 描述 SQL_LENGTH_LIMIT 100 SQL长度超过限制的长度,默认为32KB。COMMIT_ERROR_DATA_LIST 101 提交中某些数据出现异常,会返回异常的数据,通过 e.getErrData()即可获得异常数据List。此错误码...

基于Client SDK数据写入

表 3.Adb4pgClient 类 接口名称 描述 addRow(Row row,String tableName,String schemaName)/addRows(List<Row>rows,String tableName,String schemaName)插入对应表的Row格式化的数据,即一条记录,数据会存储在SDK的缓冲区中,等待commit...

DQL操作常见问题

横向合并可以通过 row_number 函数实现,两个表都新加一个ID列,进行ID关联,然后取两张表的字段。更多信息,请参见 并集 或 ROW_NUMBER。在执行UNION ALL操作时,报错ValidateJsonSize error,如何解决?问题现象 执行包含200个UNION All...

数据倾斜调优

数据倾斜排查及解决方法 根据使用经验总结,引起数据倾斜的主要原因有如下几类:Join GroupBy Count(Distinct)ROW_NUMBER(TopN)动态分区 其中出现的频率排序为 JOIN>GroupBy>Count(Distinct)>ROW_NUMBER>动态分区。Join 针对Join端产生...

与Hive、MySQL、Oracle内建函数对照表

RANK DENSE_RANK DENSE_RANK RANK RANK RANK RANK LAG LAG LAG LAG LEAD LEAD LEAD LEAD PERCENT_RANK PERCENT_RANK PERCENT_RANK PERCENT_RANK ROW_NUMBER ROW_NUMBER ROW_NUMBER ROW_NUMBER CLUSTER_SAMPLE 无 无 无 CUME_DIST CUME_DIST...

Inventory Hint

TARGET_AFFECT_ROW(NUMBER)条件Hint为TARGET_AFFECT_ROW(NUMBER):如果当前语句影响行数是指定的就成功,否则语句失败。语法:/*+TARGET_AFFECT_ROW(NUMBER)*/示例:UPDATE/*+TARGET_AFFECT_ROW(1)*/T SET c=c-1 WHERE id=1;注意事项 Hint...

内建函数概述

函数 功能 ROW_NUMBER 计算行号。从1开始递增。RANK 计算排名。排名可能不连续。DENSE_RANK 计算排名。排名是连续的。PERCENT_RANK 计算排名。输出百分比格式。CUME_DIST 计算累计分布。NTILE 将数据顺序切分成N等份,返回数据所在等份的...

Quick BI中ClickHouse数据源自定义SQL创建数据集可以...

Data truncation:Data too long for column 'sql_text' at row 1;nested exception is com.mysql.jdbc.MysqlDataTruncation: Data truncation: Data too long for column 'sql_text' at row 1 \torg.springframework.jdbc.support....

Quick BI中ClickHouse数据源使用SQL可以执行成功但是...

问题描述 Quick BI中ClickHouse数据源使用SQL可以执行成功但是创建数据集无法保存,报错“Data too long for column 'sql_text'”。报错日志如下:{"traceId":"de31655e-3180-4194-9432-9773658b8d0c","code":"AE0510100008","message":...

DBMS_SQL

DBMS_OUTPUT.PUT_LINE('last count is:'|DBMS_SQL.LAST_ROW_COUNT());END LOOP;DBMS_SQL.CLOSE_CURSOR(c);END;c1:num1,c2:1-last count is:1-c1:num2,c2:2-last count is:2-c1:num3,c2:3-last count is:3-c1:num4,c2:4-last count is:4-c1:...

RDS(MySQL)

DriverManager,PreparedStatement} import java.util.Properties import org.apache.spark.sql.types.{IntegerType,StringType,StructField,StructType} import org.apache.spark.sql.{Row,SQLContext}/链接数据库配置信息;val dbName=...

内建函数常见问题

您可以使用ROW_NUMBER函数设置自增序列,请参见 ROW_NUMBER。如何连接相同字段?您可以使用WM_CONCAT函数连接相同字段,请参见 WM_CONCAT。MaxCompute是否支持MD5函数?支持,请参见 MD5。如何实现对固定长度字符串,不足部分前面补零?您...

dbms_sql.add_trace

select*from mysql.sql_sharing\G 执行结果如下:*1.row*Id:(id number)Sql_id:82t4dswtqjg02 Schema_name:test Type:SQL_TRACE Digest_text:SELECT*FROM `t` WHERE `c1`>?AND `c1`?Plan_id:NULL Plan:NULL Version:0 Create_time:2022-11-...
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