How Can Suffix Array Indexing Enhance MySQL 'LIKE' Queries with Wildcards?

Improving MySQL Search Efficiency with "LIKE" and Wildcards

Problem: Queries such as "SELECT * FROM sometable WHERE somefield LIKE '%value%'" are inefficient due to the leading wildcard preventing index utilization.

Solution: Suffix Array Indexing

For relatively short strings, consider storing all possible suffixes of each word in the database. For instance, for the word "value", we would store:

value
alue
lue
ue
e

By storing suffixes, we eliminate the leading wildcard, enabling index usage for fast substring searches.

Storage Cost:

The storage space required for storing suffixes increases quadratically with the string length. For example:

• A 3-letter word requires a 1.5 times increase
• A 5-letter word requires a 2.5 times increase
• A 7-letter word requires a 3.5 times increase

Considerations:

• Determine how to split "words" to handle hyphenated terms.
• The trade-off between splitting and storage space efficiency should be considered.
• Removing hyphens for consistency in search queries provides increased flexibility.
• Advanced suffix array storage methods with reduced overhead may exist.

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