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select version();
| version() |
|---|
| 10.4.26-MariaDB-1:10.4.26+maria~deb10-log |
CREATE AGGREGATE FUNCTION json_merge_preserve_agg(j TINYTEXT) RETURNS TEXT DETERMINISTIC
BEGIN
DECLARE r TEXT;
DECLARE CONTINUE HANDLER FOR NOT FOUND return r;
LOOP
FETCH GROUP NEXT ROW;
IF r IS NULL THEN
SET r = j;
ELSE
SET r = JSON_MERGE_PRESERVE(r, j);
END IF;
END LOOP;
END
create table j (t text);
insert into j values ('[1, 2]'),('[2, 4]');
Records: 2 Duplicates: 0 Warnings: 0
select json_merge_preserve_agg(t) from j;
| json_merge_preserve_agg(t) |
|---|
| [1, 2, 2, 4] |