SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea4cb3fab3eeae3ef1a67d0a0849c6bd4b4669699971a4f40e0eec1729889973' 
  AND token = 'AOfGP4BAXajyG8tJvF3eW8U+GDU4gZ0ECVX+HDLSCr4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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