How can I optimize MySQL searches using 'LIKE' and wildcards?

Optimizing MySQL Search Using "LIKE" and Wildcards

Queries utilizing the "LIKE" operator with wildcards, such as "%value%", often pose optimization challenges due to the leading wildcard which hinders index usage.

Solution

If the search strings are relatively short and storage space is ample, consider the following approach:

1. Create Suffix Database:
   For each word to be stored, derive all possible suffixes by progressively removing the first character from the word.
2. Store Suffixes:
   Store each suffix in the database.
3. Search Using Suffixes:
   To search for substrings, use a "LIKE" query with a suffix wildcard, e.g., "alu%", which will find "alu" within "value."

Benefits

This technique eliminates the leading wildcard, allowing index utilization for fast lookups, but it comes at the cost of additional storage space.

Storage Considerations

The storage requirement for this approach increases quadratically with the word length. For instance, a 5-letter word will require 2.5 times more storage compared to storing the original word.

Hyphen Handling

In cases where hyphens appear, a compromise must be made between storage efficiency and search flexibility. Storing words with hyphens intact sacrifices storage space, while removing hyphens limits certain search scenarios.

Alternative Approaches

While suffix arrays offer a storage-efficient solution for suffix retrieval, their direct applicability to databases has yet to be fully explored.

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