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SELECT 
  1 
FROM 
  tmall_lock_keys 
WHERE 
  key_id = '83704c804fccf130839fe0c594126e7a827347a8552c4f256abdd0d5b9a47114' 
  AND token = 'Mk3ApdaFGKCT1gDrnwiGJcm+mrk67HO6/+d0CI1FBTg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00760

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}