SELECT 
  1 
FROM 
  tmall_lock_keys 
WHERE 
  key_id = 'e6847d80a01aabc641a491876db706233c78ae084f4766fb723e29fe08bade4a' 
  AND token = 'ReOzWHJB6KxECBhipvABRNRo6e+HffJ/aUBqxe+u7QE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00795

JSON explain

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