How Can I Efficiently Query a Database Column Containing Comma-Separated Values?

Handling Queries with Multiple Values in a Single Column

In this scenario, we encounter a table with a column named "children" that stores comma-separated names. The objective is to retrieve records where a specified child, say "Alex," exists within this column.

However, using a simple equality check (e.g., "WHERE children = 'Alex'") fails since multiple names are present in each cell. Basic LIKE searches ("WHERE children LIKE '%Alex%'") lead to false positives due to partial matches (e.g., "Alexandre" or "Diana").

To address this challenge, the optimal approach would be to normalize the data structure by introducing a separate table to store the child-parent relationships. This would allow us to efficiently perform joins and retrieve the desired information.

Nevertheless, if normalization is not feasible, a solution using the FIND_IN_SET function is presented:

WHERE FIND_IN_SET('Alex', children) > 0

This function searches for the specified string within the column value and returns a positive number if the string is present. By incorporating this condition in the WHERE clause, we can identify rows where the "Alex" child is listed.

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