mysql pgsql json array specified condition traversal query through select specified condition to perform traversal query matching in json array, without writing additional functions

Database server environment

database	Version
mysql	5.7.34
PostgreSQL	10.3

Original table structure and data

create table students
    (
        name varchar,
        gender varchar,
        age int,
        scores jsonb
);

INSERT INTO public.students (name, gender, age, scores) VALUES ('张三', '男', 34, '[{"语文": "78"},{"数学": "90"}]');
INSERT INTO public.students (name, gender, age, scores) VALUES ('李四', '女', 21, '[{"语文": "89"},{"数学": "67"}]');
INSERT INTO public.students (name, gender, age, scores) VALUES ('王二', '女', 27, null);

select *
from students ;

students

name	gender	age	scores
Zhang San	male	34	[{"Chinese": "78"}, {"Mathematics": "90"}]
John Doe	female	21	[{"Chinese": "89"}, {"Mathematics": "67"}]
Wang Er	female	27	NULL

pgsql

SQL

select *, (scores -> 0 )->>'语文' ::text as score
from students
where scores is not null
  AND exists(
        select 1
        from jsonb_array_elements(students.scores) r
        where r->>'语文' > '80'
    );

result

name	gender	age	scores	score
John Doe	female	21	[{"Chinese": "89"}, {"Mathematics": "67"}]	89

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mysql(TODO。。。

SQL

result

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