Before ETL, scripts were written individually in C or COBOL to transfer data between specific systems. This resulted in multiple databases running numerous scripts. Early ETL tools ran on mainframes as a batch
In the previous chapter, we discussed how to extract data from a source table and transform that data using SQL programming statements. This is a very traditional approach and works well for many professionals, particularly SQL programmers, but can feel cumbersome and tedious to work with....
Data Accuracy Testing(数据准确性测试)该类型测试验证数据正确的完成加载和按预期目标进行转换。Data Transformation Testing(数据转换测试)测试数据转换是一个复杂的过程，并不是简单的写一个源SQL查询并与目标进行比较来实现的。可能需要为每个行运行多个SQL查询，来验证转换规则Data Quality Testing（数据质量测试）数据...
create_engine()用于创建数据库连接。 to_sql()将dataDataFrame的数据加载到指定的target_table中,if_exists='replace'表示如果表存在则替换。 技术架构关系图 接下来,我们用Mermaid语法展示ETL项目的基本架构。 DATA_SOURCEstringsourceIdPKstringsourceNameEXTRACTstringextractIdPKstringprocessIdFKTRANSFORMstringtransformId...
In addition to notification and detailed localization of errors in the process, automatic documentation is also part of the process. 除了通知和详细定位流程中的错误外,自动文档也是流程的一部分。 Ideally, a retry should be initiated automatically after a given time window, so that short-term system ...
Error: 0xC0047022 at Load Corporate Data, DTS.Pipeline: The ProcessInput method on component "Fix Bad Records" (87) failed with error code 0xC0209029. The identified component returned an error from the ProcessInput method. The error is specific to ...
What steps do you take to determine the bottleneck of a slow running ETL process? 如果ETL进程运行较慢,需要分哪几步去找到ETL系统的瓶颈问题。 答:ETL系统遇到性能问题,运行很慢是一件较常见的事情,这时要做的是逐步找到系统的瓶颈在哪里。 首先要确定是由CPU、内存、I/O和网络等产生的瓶颈,还是由ETL处...
使用 Process Flow Editor,您可以学习如何设计将映射与其他活动互联的进程流。在本教程中,您将学习如何创建映射,以便从源中提取数据、转换数据并将其加载到目标中。本文还简要说明了 Debugging Editor,以在 Mapping Editor 中调试数据流。 所需时间:大约60 分钟注: 本教程及其设置脚本仅支持 OWB 11g 第1 版。该...
在【The fields to process】表中设置字段参数,在表第1行,单击【In steam field】输入框,在输入流字段中选中“籍贯”字段,单击【Trim type】输入框,在选项中选中“both”,其他参数使用默认值。此时完成【字符串操作】组件参数的设置,如图所示。 3)预览结果数据 在【字符串操作】转换工程中,单击【字符串操作】...
在流式ETL页面的SQL命令窗口,添加用于配置ETL任务的SQL语句。 本案例以如下SQL语句为例,配置ETL任务,将流表test_orders与维表product结合至目标表test_orders_new中。 重要 SQL语句间需以英文分号(;)分割。 CREATE TABLE `etltest_test_orders` ( `order_id` BIGINT, `user_id` BIGINT, `product_id` BIG...