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  1. MariaDB Server
  2. MDEV-30830

ANALYZE FORMAT=JSON: r_unpack_time_ms is empty for the hashed joins

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    Description

      create table t10 (
        a int, 
        b int
      );
      insert into t10 select seq, seq/3 from seq_0_to_999;
       
      create table t11 (
        a int,
        b int
      );
      insert into t11 select seq, seq/5 from seq_0_to_999;
      set join_cache_level=6;
      analyze format=json
      select * from t10, t11 
      where 
       t10.a < 700 and 
       t11.a < 100 
       and t10.b=t11.b;
      

      will produce

            {
              "block-nl-join": {
                "table": {
                  "table_name": "t11",
                  "access_type": "hash_ALL",
                  "key": "#hash#$hj",
                  "key_length": "5",
                  "used_key_parts": ["b"],
                  "ref": ["test.t10.b"],
                  "loops": 1000,
                  "r_loops": 1,
                  "rows": 1000,
                  "r_rows": 1000,
                  "cost": 9.5143874,
                  "r_table_time_ms": 0.117991585,
                  "r_other_time_ms": 0.403368737,
                  "filtered": 100,
                  "r_filtered": 10,
                  "attached_condition": "t11.a < 100"
                },
                "buffer_type": "flat",
                "buffer_size": "36Kb",
                "join_type": "BNLH",
                "attached_condition": "t11.b = t10.b",
                "r_filtered": 100,
                "r_unpack_time_ms": 0
              }
            }
      

      Note the

                "r_unpack_time_ms": 0
      

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              psergei Sergei Petrunia
              psergei Sergei Petrunia
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                Created:
                Updated:
                Resolved:

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