How to work with recursive query in MySql?

    WITH RECURSIVE transitive_closure(a, b, distance, path_string) AS
( SELECT a, b, 1 AS distance,
         a || '.' || b || '.' AS path_string,
         b AS direct_connection
    FROM edges2
   WHERE a = 1 -- set the starting node

   UNION ALL

  SELECT tc.a, e.b, tc.distance + 1,
         tc.path_string || e.b || '.' AS path_string,
         tc.direct_connection
    FROM edges2 AS e
    JOIN transitive_closure AS tc ON e.a = tc.b
   WHERE tc.path_string NOT LIKE '%' || e.b || '.%'
     AND tc.distance < 3
)
SELECT * FROM transitive_closure
--WHERE b=3  -- set the target node
ORDER BY a,b,distance

How to run this query in MySql?

You receive an error message that resembles the following:

# 1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'RECURSIVE transitive_closure (a, b, distance, path_string) AS (SELECT a, b, 1 A' at line 1
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1 answer

The operator / method is WITH RECURSIVEapplicable in PostgreSQL and Sybase (and maybe a few more, I think), so maybe you can look at this:

http://www.artfulsoftware.com/mysqlbook/sampler/mysqled1ch20.html

, MySQL ( PHP, - , )

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Source: https://habr.com/ru/post/1526045/


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