SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e5ae4acfaab3840250a1abe57cc528ddf73ab240e0b96f524527944c4472cfe' 
  AND token = 'CmgxCnTBtR0XCfgsC5eedQ+pI4PbmEQ4qZ1dKg2VInQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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