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# SHOW EXPORT
## description
    该语句用于展示指定的导出任务的执行情况
    语法：
        SHOW EXPORT
        [FROM db_name]
        [
            WHERE
            [EXPORT_JOB_ID = your_job_id]
            [STATE = ["PENDING"|"EXPORTING"|"FINISHED"|"CANCELLED"]]
        ]
        [ORDER BY ...]
        [LIMIT limit];
        
    说明：
        1) 如果不指定 db_name，使用当前默认db
        2) 如果指定了 STATE，则匹配 EXPORT 状态
        3) 可以使用 ORDER BY 对任意列组合进行排序
        4) 如果指定了 LIMIT，则显示 limit 条匹配记录。否则全部显示

## example
    1. 展示默认 db 的所有导出任务
        SHOW EXPORT;
        
    2. 展示指定 db 的导出任务，按 StartTime 降序排序
        SHOW EXPORT FROM example_db ORDER BY StartTime DESC;

    3. 展示指定 db 的导出任务，state 为 "exporting", 并按 StartTime 降序排序
        SHOW EXPORT FROM example_db WHERE STATE = "exporting" ORDER BY StartTime DESC;
    
    4. 展示指定db，指定job_id的导出任务
            SHOW EXPORT FROM example_db WHERE EXPORT_JOB_ID = job_id;

## keyword
    SHOW,EXPORT