Apparatus and methods of use for index key generation for identifiers containing metadata elements

A computer implemented method, executed by at least one processor and utilizing a non-transitory computer-readable medium that stores program instructions, of using index key generation for identifiers containing metadata elements from a crime lab, comprising the steps:

• a. Feeding existing identifiers being into a deterministic process and creating unique compound lexical identifiers in an index;
• b. Recovering an item from a scene A identified as A001.1, where 001. as item #1, and .1 as cutting #1 from item #1;
• c. Providing a numbering and sub sampling comprise an unlimited number of levels deep;
• d. Obtaining the next item for scene A by search in the index for A* ordered descending, returning a top row only;
• e. Obtaining the next sub item (cutting) for item #2 from scene A by searching in the index for A002*, ordered descending and returning the top row only.

A computer-implemented method, computer implemented method, executed by at least one processor and utilizing a non-transitory computer-readable medium that stores program instructions, using index key generating lexically sortable index keys for original identifiers that each include metadata, the method comprising:

• a. receiving each original identifier that includes a plurality of alphanumeric sections separated by separator characters;
• b. parsing the received identifier into constituent sections that include numeric subsections and alphabetic subsections;
• c. for every numeric subsection, removing leading zero characters and determining a length of the resulting numeric subsection;
• d. for every alphabetic subsection, determining a length of the alphabetic subsection;
• e. assigning, to each subsection, a section-length prefix selected from (i) a first lookup table that maps numeric subsection lengths of 1–15 to the characters 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, and F and (ii) a second lookup table that maps alphabetic subsection lengths of 1–15 to the characters J, K, L, M, N, O, P, Q, R, S, T, U, V, W, and X;
• f. when a subsection exceeds fifteen characters in length, appending an escape prefix that is (i) the character G for numeric subsections or (ii) the character Y for alphabetic subsections, followed by a two-digit base-36 representation of the subsection length;
• g. for a decimal numeric subsection, omitting the section-length prefix for digits occurring after a decimal point, appending a suffix character having an ASCII value lower than any numeric character, and removing trailing zero characters from the decimal portion;
• h. concatenating, in the original left-to-right order, the prefixes generated in steps (e)–(g) with their corresponding subsections to form a “lexical index key” that uniquely represents the original identifier;
• i. selectively overriding natural sort order by substituting (i) prefix 0 to force the lexical index key to a first position or (ii) prefix Z to force the lexical index key to a last position in a sorted list;
• j. storing each lexical index key in a computer-readable medium as an element of an index such that lexicographic sorting of the lexical index keys produces the natural ordering of the original identifiers;
• and
• k. searching the index for a query identifier by generating, according to steps (a)–(h), a query lexical index key and performing a lexicographic lookup of the query lexical index key, whereby identifiers that differ only in leading-zero padding resolve to an identical lexical index key.