Why is the SQL trace plan NULL in PolarDB?
* 7. row * TYPE: SQL SQL_ID: 5dd0natwyujq5 SCHEMA_NAME: echemi_db_v0_3 DIGEST_TEXT: SELECT sdt . produce_id , sdt . customer_id , sel . company_name AS company_name_m , sel . prefix_domain_name , sdt . products_id , sdt . products_url_name , SUBSTRING ( sdt . category_id , ?, … ) AS category_id_lv1 , sdt . produce_cas_no AS cas_no […]