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CREATE TABLE test_tbl(
id INT,
data json );
insert into test_tbl values
(1,'{"field1": "123432", "field2":"TEST", "field3": "", "field4": "JAMES"}'),
(2,'{"field1": "123432", "field2":"TEST", "field3": "TEST", "field4": "JAMES"}');
select JSON_UNQUOTE(JSON_EXTRACT(data, '$.field3'))
from test_tbl
where JSON_UNQUOTE(JSON_EXTRACT(data, '$.field3')) !='' ;
| JSON_UNQUOTE(JSON_EXTRACT(data, '$.field3')) |
|---|
| TEST |