How Can I Efficiently Combine LIKE and IN Operators in SQL Queries?

Combination of "LIKE" and "IN" expressions in SQL

In SQL, the LIKE operator is used to perform pattern-based string matching, while the IN operator checks if a value matches any value in a specified list of values. However, there is no direct way to combine these two operators into a single expression.

A common solution is to use a series of OR statements with the LIKE operator, for example:

<code class="language-sql">WHERE something LIKE 'bla%' OR something LIKE '%foo%' OR something LIKE 'batz%'</code>

This approach is verbose and can become unwieldy when the number of patterns is large. A more flexible and readable solution is to use a subquery:

<code class="language-sql">SELECT * FROM table WHERE something IN (
  SELECT * FROM (VALUES ('bla%'), ('%foo%'), ('batz%')) AS patterns(pattern)
)</code>

However, in some database systems there may be a more efficient option called Full Text Search (FTS). Both Oracle and SQL Server provide FTS implementations that provide enhanced functionality for searching text data.

Use FTS combined with LIKE and IN

FTS allows more complex pattern matching and includes a special operator called CONTAINS. This operator allows you to combine multiple patterns into a single expression, effectively combining the functionality of LIKE and IN.

In Oracle, the syntax for using CONTAINS is:

<code class="language-sql">WHERE CONTAINS(column, 'pattern1 OR pattern2 OR ...') > 0</code>

In SQL Server, the syntax is slightly different:

<code class="language-sql">WHERE CONTAINS(column, '"pattern1*" OR "pattern2*" OR ...')</code>

By using FTS, you can create cleaner, more efficient queries that can search multiple patterns in one step. This can significantly improve performance, especially on large data sets with complex search conditions.

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