1.1.6 Discuss problems that may arise as a part of data migration.
The process of transporting data between computers, storage devices or formats. It is a key consideration for any system implementation, upgrade or consolidation.
Usually performed programmatically to achieve an automated migration, freeing up human resources from tedious tasks.
Software programs or scripts are used to map system data for automated migration.
Assess ⇒ Plan ⇒ Extract ⇒ Cleanse ⇒ Load ⇒ Verify
Planning issues cause insufficient time and resources allocated to migration of data between systems.
Incomplete data transfer and / or data glitches can lead to poor data quality and lost data.
Inadequate testing may occur before and after migration.
Extended downtime may occur as the data is in the process of being migrated.
The recorded information that exists in your current storage system.
Can include database records, spreadsheets, text files, scanned images and paper documents.
All these data formats can be migrated to a new system.
The process of importing legacy data to a new system.
This can involve entering the data manually, moving disk files from one folder or computer to another, database insert queries, developing custom software, etc.
The specific method used for any particular system depends entirely on the systems involved and the nature and state of the data being migrated.
The process of preparing legacy data for migration to a new system.
Different architecture and storage methods of new or updated systems cause legacy data to not meet the criteria set by the new system or is incompatible with it, thus it must be modified prior to migration.
Architecture differences include incompatible file formats, different data structures, design flaws in the legacy system, etc.
Process manipulates or cleans the legacy data so it conforms to the new system’s requirements.
The process of ensuring that a program operates on clean, correct and useful data.
Ensures that the data meets a set of criteria, often called “validation rules”.
A new system always requires a correct character set--this is often an issue when migrating data.
A computer stores all data as (binary) numbers.
A character set is a mapping of text, digits and symbols to a numeric value that can be stored by a computer.
A character set is created through a process known as encoding i.e. each character is assigned with a unique value.
The American Standard Code for Information Interchange (ASCII) is one of the most popular character encoding sets. It represents uppercase and lowercase English alphabets, number, mathematical operators and symbols from integers with values between 0 and 127.
Is a modern standard for text representation that defines each of the letters and symbols commonly used in today’s digital and print media. It is the top standard for identifying characters in text in nearly any language. It allows for the representation of diverse languages regardless of the characters used, such as Hebrew, Arabic and Chinese.
In data migration, conversions between ASCII and Unicode may occur.
This occurs especially when a company expands into new international markets and text is required to be stored in multiple languages.
ASCII uses an 8-bit encoding while Unicode uses a variable bit encoding.
Unicode is standardized while ASCII isn’t.
Unicode represents most written languages in the world while ASCII does not.
ASCII has its equivalent within Unicode.
Are means of adapting computing systems to different languages, regional differences (e.g. currency) and technical requirements of a target market.
Internationalization - The process of designing a software application so that it can potentially be adapted to various languages and regions without engineering changes.
Localization - The process of adapting internationalized software for a specific region.