SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '104ae4864baae58a7662d6ed38a7226a912178131fd98826b80bbd718819f554' 
  AND token = 'jdQ8BoYAUtsVm3PTtZgc7HMnp1w0vubAbKnjqX9PFos=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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