Statistics
https://play.clickhouse.com/play?user=play#c2VsZWN0IAp0b1N0YXJ0T2ZIb3VyKGNoZWNrX3N0YXJ0X3RpbWUpIGFzIGQsCmNvdW50KCksICBncm91cFVuaXFBcnJheShwdWxsX3JlcXVlc3RfbnVtYmVyKSwgIGFueShyZXBvcnRfdXJsKQpmcm9tIGNoZWNrcyB3aGVyZSAnMjAyMi0wNi0wMScgPD0gY2hlY2tfc3RhcnRfdGltZSBhbmQgdGVzdF9uYW1lIGxpa2UgJyUwMjQ5MV9wYXJ0X2xvZ19oYXNfdGFibGVfdXVpZCUnIGFuZCB0ZXN0X3N0YXR1cyBpbiAoJ0ZBSUwnLCAnRkxBS1knKSBncm91cCBieSBkIG9yZGVyIGJ5IGQgZGVzYw==

Some times there are not output from requests.
{
        
        NOT_A_MERGE = 1,
        
        REGULAR_MERGE = 2,
        
        TTL_DELETE_MERGE = 3,
        
        TTL_RECOMPRESS_MERGE = 4,
    };
    String query_id;
    Type event_type = NEW_PART;
    MergeReasonType merge_reason = NOT_A_MERGE;
    PartMergeAlgorithm merge_algorithm = UNDECIDED;
    time_t event_time = 0;
    Decimal64 event_time_microseconds = 0;
    UInt64 duration_ms = 0;
    String database_name;
    String table_name;
    String part_name;
    String partition_id;
    String disk_name;
    String path_on_disk;
    MergeTreeDataPartType part_type;
    
    UInt64 rows = 0;
    
    UInt64 bytes_compressed_on_disk = 0;
    
    Strings source_part_names;