SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '110c11c837c0c561225598b57805f0d7eb6b22ce680d8f0b0e57eb63c7c27432' 
  AND token = 'GtrtLnaiNduEma7GsPo9uRHSKHXy5aiWH//tjsCXJcE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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