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drop table if exists t0,t1,t2;
#
# MDEV-7266: Assertion `!element_started' failed in Json_writer& Json_writer::add_member
#
CREATE TABLE t1 (a INT) ENGINE=InnoDB;
INSERT INTO t1 VALUES (1),(2);
CREATE TABLE t2 (column_name_1 INT, column_name_2 VARCHAR(52)) ENGINE=InnoDB;
INSERT INTO t2 VALUES (3,'United States');
CREATE TABLE t3 (b INT, c VARCHAR(3), PRIMARY KEY (c,b)) ENGINE=InnoDB;
INSERT INTO t3 VALUES (4,'USA'),(5,'CAN');
EXPLAIN FORMAT=JSON SELECT * FROM t1 WHERE 0 < ALL (
SELECT tbl_alias1.column_name_1 FROM t2 AS tbl_alias1, t3 AS tbl_alias2
WHERE tbl_alias2.b = tbl_alias1.column_name_1 AND tbl_alias2.c = tbl_alias1.column_name_2
);
EXPLAIN
{
"query_block": {
"select_id": 1,
"nested_loop": [
{
"table": {
"table_name": "t1",
"access_type": "ALL",
"rows": 2,
"filtered": 100
}
}
],
"subqueries": [
{
"query_block": {
"select_id": 2,
"nested_loop": [
{
"table": {
"table_name": "tbl_alias1",
"access_type": "ALL",
"rows": 1,
"filtered": 100,
"attached_condition": "tbl_alias1.column_name_2 is not null and tbl_alias1.column_name_1 is not null"
}
},
{
"table": {
"table_name": "tbl_alias2",
"access_type": "eq_ref",
"possible_keys": ["PRIMARY"],
"key": "PRIMARY",
"key_length": "9",
"used_key_parts": ["c", "b"],
"ref": [
"test.tbl_alias1.column_name_2",
"test.tbl_alias1.column_name_1"
],
"rows": 1,
"filtered": 100,
"attached_condition": "tbl_alias2.c = tbl_alias1.column_name_2",
"using_index": true
}
}
]
}
}
]
}
}
drop table t1,t2,t3;
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