[MDEV-26711] JSON histograms become invalid due to not properly quoted values - Jira

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JSON histograms turn out invalid if a column value contains, for example, a double quote mark.

create or replace table t (a varchar(32));

insert into t values ('this is "quoted" text');

set histogram_type= JSON_HB;

analyze table t persistent for all;

select * from t where a = 'foo';

# Cleanup

drop table t;

preview-10.7-MDEV-26519-json-histograms da8bb4b4703
MariaDB [test]> select * from t where a = 'foo';
ERROR 4183 (HY000): Failed to parse histogram: Root JSON element must be a JSON object at offset 0.

is caused by

MDEV-21130 Histograms: use JSON as on-disk format

MDEV-26519 JSON Histograms: improve histogram collection