Improving data cleaning quality using a data lineage facility

Lecture Notes in Computer Science, 2011

Data cleaning and ETL processes are usually modeled as graphs of data transformations. The involvement of the users responsible for executing these graphs over real data is important to tune data transformations and to manually correct data items that cannot be treated automatically. In this paper, in order to better support the user involvement in data cleaning processes, we equip a data cleaning graph with data quality constraints to help users identifying the points of the graph and the records that need their attention and manual data repairs for representing the way users can provide the feedback required to manually clean some data items. We provide preliminary experimental results that show the significant gains obtained with the use of data cleaning graphs.

2011

Data cleaning and ETL processes are usually modeled as graphs of data transformations. The involvement of the users responsible for executing these graphs over real data is important to tune data transformations and to manually correct data items that cannot be treated automatically. In this paper, in order to better support the user involvement in data cleaning processes, we equip a data cleaning graph with data quality constraints to help users identifying the points of the graph and the records that need their attention and manual data repairs for representing the way users can provide the feedback required to manually clean some data items. We provide preliminary experimental results that show the significant gains obtained with the use of data cleaning graphs.

2010

Data cleaning and Extract-Transform-Load processes are usually modeled as graphs of data transformations. These graphs typically involve a large number of data transformations, and must handle large amounts of data. The involvement of the users responsible for executing the corresponding programs over real data is important to tune data transformations and to manually correct data items that cannot be treated automatically.

We classify data quality problems that are addressed by data cleaning and provide an overview of the main solution approaches. Data cleaning is especially required when integrating heterogeneous data sources and should be addressed together with schema-related data transformations. In data warehouses, data cleaning is a major part of the so-called ETL process. We also discuss current tool support for data cleaning.

Proceedings of the 2014 ACM SIGMOD International Conference on Management of Data, 2014

Data cleaning techniques usually rely on some quality rules to identify violating tuples, and then fix these violations using some repair algorithms. Oftentimes, the rules, which are related to the business logic, can only be defined on some target report generated by transformations over multiple data sources. This creates a situation where the violations detected in the report are decoupled in space and time from the actual source of errors. In addition, applying the repair on the report would need to be repeated whenever the data sources change. Finally, even if repairing the report is possible and affordable, this would be of little help towards identifying and analyzing the actual sources of errors for future prevention of violations at the target. In this paper, we propose a system to address this decoupling. The system takes quality rules defined over the output of a transformation and computes explanations of the errors seen on the output. This is performed both at the target level to describe these errors and at the source level to prescribe actions to solve them. We present scalable techniques to detect, propagate, and explain errors. We also study the effectiveness and efficiency of our techniques using the TPC-H Benchmark for different scenarios and classes of quality rules. * Work partially done while at QCRI.

International Journal of Computer Applications, 2013

Data Cleansing or (data scrubbing) is an activity involving a process of detecting and correcting the errors and inconsistencies in data warehouse. Thus poor quality data i.e.; dirty data present in a data mart can be avoided using various data cleaning strategies, and thus leading to more accurate and hence reliable decision making. The quality data can only be produced by cleaning the data and pre-processing it prior to loading it in the data warehouse.

ITEGAM- Journal of Engineering and Technology for Industrial Applications (ITEGAM-JETIA), 2020

One of the great challenges to obtaining knowledge from data sources is to ensure consistency and non-duplication of stored information. Many techniques have been proposed to minimize the work cost and to allow data to be analyzed and properly corrected. However, there are still other essential aspects for the success of data cleaning process that involve many technological areas: performance, semantic and autonomy of the process. Against this backdrop, we developed an automated configurable data cleaning environment based on training and physical-semantic data similarity, aiming to provide a more efficient and extensible tool for performing information correction which covers problems not yet explored such as semantic and autonomy of the cleaning implementation process. The developed work has, among its objectives, the reduction of user interaction in the process of analyzing and correcting data inconsistencies and duplications. With a properly calibrated environment, the efficiency is significant, covering approximately 90% of inconsistencies in the database, with a 0% percentage of false-positive cases. Approaches were also demonstrated to show that besides detecting and treating information inconsistencies and duplication of positive cases, they also addressed cases of detected false-positives and the negative impacts they may have on the data cleaning process, whether manual or automated, which is not yet widely discussed in literature. The most significant contribution of this work refers to the developed tool that, without user interaction, is automatically able to analyze and eliminate 90% of the inconsistencies and duplications of information contained in a database, with no occurrence of false-positives. The results of the tests proved the effectiveness of all the developed features, relevant to each module of the proposed architecture. In several scenarios the experiments demonstrated the effectiveness of the tool.

International Journal of Computer Applications, 2013

Data assessment and data cleaning tasks have traditionally been addressed through procedural solutions. Most of the time, those solutions have been applicable to specific problems and domains. In the last few years we have seen the emergence of more generic solutions; and also of declarative and rule-based specifications of the intended solutions of data cleaning processes. In this chapter we review some of those recent developments.

International Journal of Knowledge-Based Organizations, 2011

The quality of real world data that is being fed into a data warehouse is a major concern of today. As the data comes from a variety of sources before loading the data in the data warehouse, it must be checked for errors and anomalies. There may be exact duplicate records or approximate duplicate records in the source data. The presence of incorrect or inconsistent data can significantly distort the results of analyses, often negating the potential benefits of information-driven approaches. This paper addresses issues related to detection and correction of such duplicate records. Also, it analyzes data quality and various factors that degrade it. A brief analysis of existing work is discussed, pointing out its major limitations. Thus, a new framework is proposed that is an improvement over the existing technique.