


Can I Join Tables with Semi-colon Separated Values in a Column Using Pure MySQL?
Can I resolve this with pure mysql? (joining on ';' separated values in a column)
Question:
Given two tables, a user table t1 with a resources column containing ';' separated resource IDs, and a resource table t2 with an ID and data, you want to join t1 and t2 to get a table with user and resource data.
Problem:
You can't use external languages to manipulate the results and the user_resources table is denormalized.
Solution:
Create a table called integerseries with numbers from 1 to a certain limit. Use COUNT_IN_SET and VALUE_IN_SET functions, which treat the resources column as an array, to normalize the table. Then join with integerseries to extract individual resource IDs.
<code class="sql">SELECT user_resource.user, resource.data FROM user_resource JOIN integerseries AS isequence ON isequence.id </code>
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