How Can I Efficiently Use Multiple LIKE Conditions in a Database Query?

Beyond OR: A More Efficient Approach to Multiple LIKE Conditions

Database searches often require complex criteria, frequently involving multiple LIKE conditions. While using OR is simple, it can be inefficient and less flexible for extensive pattern matching. This article presents a superior method utilizing temporary tables.

The Efficiency of Temporary Tables

To manage multiple LIKE patterns effectively, create a temporary table to store these patterns. This table, for example, could be named patterns with a single column, pattern, holding the relevant data type (e.g., VARCHAR). If your patterns are 'ABC%', 'XYZ%', and 'PQR%', the table creation and population would look like this:

<code class="language-sql">CREATE TEMPORARY TABLE patterns (
  pattern VARCHAR(20)
);

INSERT INTO patterns VALUES ('ABC%'), ('XYZ%'), ('PQR%');</code>

Joining for Pattern Matching Optimization

With the temporary table populated, a JOIN operation efficiently filters your main table (tbl) based on the patterns. Any row in tbl matching any pattern in patterns will be included in the results. The query would be:

<code class="language-sql">SELECT t.*
FROM tbl t
JOIN patterns p
ON (t.col LIKE p.pattern);</code>

Handling Duplicate Results with DISTINCT

If a column might match multiple patterns, resulting in duplicate rows, use the DISTINCT keyword to return only unique results:

<code class="language-sql">SELECT DISTINCT t.*
FROM tbl t
JOIN patterns p
ON (t.col LIKE p.pattern);</code>

Summary: A Superior Approach

Using temporary tables for managing multiple LIKE conditions offers a cleaner, more efficient, and adaptable solution. This separation of patterns simplifies management and expansion of search criteria. The result is improved query performance, readability, and maintainability.

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