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Let's assume, I have a mixed geometry type table in PostgreSQL The multipart geometries don't intersect themselves. I would like to generate a center point collection from every geometry. I know how to create centroids from singlepart geoms. But is it possible to create singlepart geoms from multipart geoms without making a new table (ST_DUMP)? And in the memory take every converted geom, and get its center point. Is it possible?

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    ST_Dump doesn't create a new table, it returns a set of results. Look at the 1st example in the doc and apply the centroid function instead of ST_AsEWKT
    – JGH
    Dec 1 '21 at 19:01
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With a LATERAL table function expression (as implicit CROSS JOIN) instead of record notation selection ((ST_Dump()).*) - flexible, fast and elegant:

SELECT t.<id>,
       ST_Centroid(dmp.geom) AS geom    -- ST_PointOnSurface(dmp.geom)
FROM   <table> AS t,
       LATERAL ST_Dump(t.<geom>) AS dmp
;

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