How Can I Optimize MySQL Searches Using 'LIKE' with Wildcards?

Optimizing MySQL Search Using "Like" and Wildcards

The "like" condition with wildcard characters can significantly impact query performance in MySQL when used with leading wildcards. The reason for this is that the leading wildcard prevents the DBMS from utilizing indexes, leaving the query to perform a linear search through the entire table.

Considering the limitations of the "like" condition with wildcards and the solidity of the string values to be searched, a different approach is required to improve performance. This approach involves creating a table of suffixes for each word to be searched.

By storing every possible suffix of each word, queries using the "like" condition with only trailing wildcards can now leverage indexes. The "like" condition will no longer be hindered by the leading wildcard, allowing for efficient lookups using a range query on the index.

The storage cost associated with this approach is a trade-off. While it eliminates the storage overhead of the leading wildcard in the "like" condition, it introduces additional storage requirements for the table of suffixes. The storage space needed increases dramatically with increasing word length.

Implementation considerations include determining the appropriate word splitting strategy (e.g., handling hyphens), balancing storage overhead with query efficiency, and exploring alternate storage methods for suffix arrays to minimize storage costs.

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