How Can I Efficiently Combine LIKE and IN Operators in SQL Server for Data Filtering?

SQL Server: Combining LIKE and IN for Data Filtering

This article explores the effective use of both LIKE and IN operators within a single SQL Server query for refined data filtering. It's important to note that directly combining these operators isn't straightforward, as their interaction differs from using multiple wildcards with LIKE.

Understanding the IN Operator

The IN operator efficiently compares a column against a set of specified values. For example:

SELECT * FROM MyTable WHERE MyColumn IN (1, 2, 3);

This query retrieves all rows where MyColumn contains 1, 2, or 3.

The Challenge of Combining LIKE and IN

While it might seem logical to combine LIKE and IN directly, this approach isn't directly supported. The IN operator functions as a series of OR conditions. Therefore:

SELECT * FROM MyTable WHERE MyColumn LIKE IN ('Text%', 'Link%', 'Hello%', '%World%'); -- Incorrect

is not valid SQL. It doesn't behave like using multiple wildcards.

The Correct Approach: Using Multiple OR Conditions

To achieve the desired filtering, use separate LIKE conditions joined by OR:

SELECT * FROM MyTable WHERE MyColumn LIKE 'Text%' OR MyColumn LIKE 'Hello%' OR MyColumn LIKE 'That%';

This correctly returns rows where MyColumn contains 'Text', 'Hello', or 'That' as a substring, anywhere within the column value. This method provides the flexibility and control needed for complex pattern matching.

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