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How Can I Generate Rows for JOINs in MySQL Without Oracle's `CONNECT BY` or Similar Functions?

Linda Hamilton
Release: 2025-01-15 10:02:43
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How Can I Generate Rows for JOINs in MySQL Without Oracle's `CONNECT BY` or Similar Functions?

MySQL JOINs: Row Generation Without Oracle's CONNECT BY

Unlike Oracle's convenient CONNECT BY LEVEL clause for generating row sets in joins, MySQL lacks a direct equivalent. Oracle's approach simplifies creating sequences for joins:

<code class="language-sql">SELECT *
FROM dual
CONNECT BY LEVEL < p></code>
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Similarly, MS SQL Server uses recursion:

<code class="language-sql">WITH hier(row) AS (
    SELECT 1
    UNION ALL
    SELECT row + 1
    FROM hier
    WHERE row < p></code>
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PostgreSQL offers generate_series:

<code class="language-sql">SELECT *
FROM generate_series(1, n)</code>
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However, MySQL requires alternative strategies for generating rows needed in JOIN operations. These often involve workarounds or external tools due to the absence of a built-in row generator.

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