U00000044

U00000044 is a generic, non-specific identifier used in data systems to tag a particular item or record. It is commonly employed in demonstrations, tutorials, and testing datasets to avoid referencing real-world identifiers. The format consists of the uppercase letter U followed by eight decimal digits, for example U00000001 or U00001234. In some systems the digits are treated as a simple numeric key, while in others they may encode subfields such as region, category, or item sequence, depending on internal schema.

Applications: U codes appear in library catalogs, digital asset management, inventory databases, and software debugging logs. They serve as stable references across logs and metadata, enabling reproducible examples and data interchange where real IDs cannot be disclosed.

Generation and governance: U codes are often produced by database sequences or ID generation services. Best practice emphasizes uniqueness, non-reassignment, and clear provenance of the code to avoid collision across datasets and over time. Some organizations maintain a centralized registry to track active codes and deprecated ones.

Limitations and interpretation: If digits encode meaning, changing the schema can break external references. Many implementations treat the code as opaque to preserve flexibility; in such cases only the string identity matters.

See also: U00000001, U00000045, Unicode notation U+#### for code points, catalog numbers.