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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a339a8a92377ce9332926b14a3e10aa4b01a9e60bf7a03b7c453a8ccde3ac04c' 
  AND token = 'Rhc5qV6ol87iNZwoEL4rT+dJ6pUTkt7Nrhqy4biy5Lo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}