Query time 0.00081
JSON explain
{
"query_block": {
"select_id": 1,
"cost_info": {
"query_cost": "21.61"
},
"grouping_operation": {
"using_temporary_table": true,
"using_filesort": true,
"cost_info": {
"sort_cost": "0.29"
},
"nested_loop": [
{
"table": {
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"access_type": "ALL",
"possible_keys": [
"thread_id",
"thread_id_2"
],
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"filtered": "10.00",
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"eval_cost": "1.14",
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"data_read_per_join": "2K"
},
"used_columns": [
"post_id",
"thread_id",
"status"
],
"attached_condition": "(`portal`.`dp`.`status` = 'A')"
}
},
{
"table": {
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"PRIMARY",
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],
"key": "PRIMARY",
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"key_length": "3",
"ref": [
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],
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"read_cost": "5.70",
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"data_read_per_join": "4"
},
"used_columns": [
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],
"attached_condition": "((`portal`.`q_discussion`.`object_id` in (1737,1747,1748,1749,1745,1751,1752,1753,1754,1931,2167,2169,2170,2171,2172,2173,2174,2175,2176,1941,2178,2179,2180,2181,2182,2183,2184,2185,2186,1951,2187,2189,2190,1955,2191,2192,2193,2194,2195,2196,2197,2198,2199,2200,2201,2203,2204,2205,1970,2206,2208,2209,2210,2211,2212,2213,2214,2215,2216,2217,2218,2219,2220,1985,2223,2224,2225,2226,2227,2228,2229,2230,2231,2232,2233,2234,2235,2236,2000,2238,2239,2240,1388,8679,8680)) and (`portal`.`q_discussion`.`object_type` = 'P'))"
}
},
{
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],
"key": "PRIMARY",
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"product_id"
],
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"ref": [
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],
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"filtered": "100.00",
"using_index": true,
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"eval_cost": "0.06",
"prefix_cost": "21.33",
"data_read_per_join": "1K"
},
"used_columns": [
"product_id"
]
}
}
]
}
}
}