mariadb/mysql-test/main/join_cache_debug.result

#
# MDEV-32351: Significant slowdown for query with many outer joins
#
CREATE TABLE t1 (b int NOT NULL, PRIMARY KEY (b)) ENGINE=MYISAM;
INSERT INTO t1 select seq from seq_1_to_10000;
CREATE TABLE t2 (b int NOT NULL, d varchar(255), KEY (b)) ENGINE=MYISAM ;
INSERT INTO t2 VALUES (1,1),(2,2),(3,3);
CREATE TABLE t3 (c int NOT NULL, PRIMARY KEY (c)) ENGINE=MYISAM ;
INSERT INTO t3 select seq from seq_1_to_3000;
CREATE TABLE t4 (c int NOT NULL, PRIMARY KEY (c)) ENGINE=MYISAM;
INSERT INTO t4 select seq from seq_1_to_3000;
ANALYZE TABLE t1,t2,t3,t4;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
test.t2	analyze	status	Engine-independent statistics collected
test.t2	analyze	status	OK
test.t3	analyze	status	Engine-independent statistics collected
test.t3	analyze	status	OK
test.t4	analyze	status	Engine-independent statistics collected
test.t4	analyze	status	OK
create table t1_t2 as
select 
t1.b as t1_b, t2.b as t2_b, t2.d as t2_d
FROM t1
LEFT JOIN t2 ON t1.b = t2.b;
SET statement debug_dbug='+d,analyze_print_r_unpack_ops' for
analyze
format=json
SELECT COUNT(*)
FROM t1_t2
LEFT JOIN t3 ON t2_d = t3.c
LEFT JOIN t4 ON t3.c=1
select '$js' as JSON;
JSON
{
  "query_block": {
    "select_id": 1,
    "r_loops": 1,
    "r_total_time_ms": "REPLACED",
    "const_condition": "1",
    "table": {
      "table_name": "t1_t2",
      "access_type": "ALL",
      "r_loops": 1,
      "rows": 10000,
      "r_rows": 10000,
      "r_table_time_ms": "REPLACED",
      "r_other_time_ms": "REPLACED",
      "r_engine_stats": REPLACED,
      "filtered": 100,
      "r_filtered": 100
    },
    "table": {
      "table_name": "t3",
      "access_type": "eq_ref",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "4",
      "used_key_parts": ["c"],
      "ref": ["test.t1_t2.t2_d"],
      "r_loops": 10000,
      "rows": 1,
      "r_rows": 0.0003,
      "r_table_time_ms": "REPLACED",
      "r_other_time_ms": "REPLACED",
      "r_engine_stats": REPLACED,
      "filtered": 100,
      "r_filtered": 100,
      "attached_condition": "trigcond(t1_t2.t2_d = t3.c and trigcond(t1_t2.t2_d is not null))",
      "using_index": true
    },
    "block-nl-join": {
      "table": {
        "table_name": "t4",
        "access_type": "index",
        "key": "PRIMARY",
        "key_length": "4",
        "used_key_parts": ["c"],
        "r_loops": 1,
        "rows": 3000,
        "r_rows": 3000,
        "r_table_time_ms": "REPLACED",
        "r_other_time_ms": "REPLACED",
        "r_engine_stats": REPLACED,
        "filtered": 100,
        "r_filtered": 100,
        "using_index": true
      },
      "buffer_type": "flat",
      "buffer_size": "256Kb",
      "join_type": "BNL",
      "attached_condition": "trigcond(trigcond(t3.c = 1))",
      "r_loops": 10000,
      "r_filtered": 0.04333,
      "r_unpack_time_ms": "REPLACED",
      "r_unpack_ops": 3000,
      "r_other_time_ms": "REPLACED",
      "r_effective_rows": 3000
    }
  }
}
# This must show 3000, not 30000000:
select json_extract('$js', '\$**.r_unpack_ops') as R_UNPACK_OPS;
R_UNPACK_OPS
[3000]
SET debug_dbug=@old_debug;
drop table t1,t2,t3,t4;
drop table t1_t2;